Results and open questions

Claims

Browse definitions, theorems, conjectures, counterexamples, and open problems from across FPRD Lab. Each record includes its exact statement, supporting evidence, dependencies, limitations, and links to related papers.

902 indexed claims and results

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A suggested reading order
  1. 01

    Automata and formal languages · proof

    A direct scaffold for even palindromes

    Conditional on the complete Draft 5 Section 11.1 sequence contract, persistent receipts and simultaneous records give a direct finite-scaffold and PEG route with symbolic resource bounds.

  2. 02

    Automata and formal languages · mechanically checked

    Strict real-time multitape machines compile to scaffolds

    A mechanically checked construction turns each fixed-tape real-time machine step into one bounded persistent scaffold update.

  3. 03

    Automata and formal languages · informal proof

    Reversed real-time multitape languages sit properly inside PEG

    The transfer theorem and classical palindrome recognition together place even palindromes in PEG.

  4. 04

    Automata and formal languages · mechanically checked

    The scaffold-to-PEG direction is mechanically checked

    The full sufficient direction of the Loff–Moreira–Reis correspondence is formalized for finite scaffolding automata.

  5. 05

    Logic, semantics, and rewriting · proof

    Local moves generate final behavioral equivalence

    In the unary distance-one setting, detours, absorptions, garbage moves, and carrier slides connect exactly the histories with the same final behavior.

  6. 06

    Logic, semantics, and rewriting · proof

    Unary scaffold histories admit a finite coherent presentation

    A finite family of cubical and bounded critical cells generates all parallel paths inside a final behavioral fibre.

  7. 07

    Algebra and discrete mathematics · proof

    Explicit metric-group products on the half-line

    A nested readout transports bitwise XOR to group laws on the nonnegative reals whose product is also a metric.

  8. 08

    Algorithms and complexity · mechanically checked

    The direct GapCVP reduction reaches 1/30-hardness

    Independently checked parameter choices preserve the direct reduction while exposing a retained-architecture frontier at 1/28.

  9. 09

    Models of computation · informal proof

    Compact finite feasibility sews into one presentation

    Under the stated compactness hypotheses, feasibility through every observation horizon yields one uniform exact presentation.

  10. 10

    Models of computation · informal proof

    Escape modulus detects failure of exact sewing

    Bounded escape identifies membership in one compact resource core; unbounded escape records finite feasibility without uniform realization.

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All claims and evidence

902 records

Search by statement, research area, result type, or contribution assessment. Each row links to its proof or evidence, sources, dependencies, limitations, and open work.

203 of 902 entries

Stable ID and statementType and current statusContribution assessmentResearch area and topicProof or evidenceDependenciesSource and reviewNext action
FPRD-D18For a generalized Dyck alphabet with k bracket types and any number of neutral symbols, the exact residual carrier consists of finite typed stacks together with an absorbing failure state. A live stack s has future language K_s of words that empty it without failure; failure has the empty future language.DefinitionPrecisely stated and self-containedEvidence and limits →Automata and formal languagesGeneralized-Dyck residual dynamicsModel and exact residualsNo recorded dependenciesFPRD Dyck-residual and finite-observation proof recordsReviewed 2026-08-25No documented external or specialist review of this FPRD result is recorded.Add a small worked residual calculation for two bracket types and one neutral symbol.
FPRD-T34Every left residual of a generalized Dyck language is exactly KsK_s for one live stack ss, or K⊥K_\bot; all are reachable and pairwise distinct. Distinct live stacks satisfy sep⁡(Ks,Kt)=min⁡(∣s∣,∣t∣)\operatorname{sep}(K_s,K_t)=\min(|s|,|t|), while sep⁡(Ks,K⊥)=∣s∣\operatorname{sep}(K_s,K_\bot)=|s|. The induced ultrametric makes openers half-contractions, neutrals isometries, and closers at most 22-Lipschitz.TheoremProved and internally auditedEvidence and limits →Automata and formal languagesGeneralized-Dyck residual dynamicsExact residual theoremFPRD-D18FPRD Dyck-residual and finite-observation proof recordsReviewed 2026-08-25No documented external or specialist review of this FPRD result is recorded.Compare the transition monoid and ultrametric formulation with standard polycyclic-monoid treatments.
FPRD-T35The depth-NN quotient keeps every stack of height at most NN and places all deeper stacks and failure in one tail class. It has 1+∑h=0Nkh1+\sum_{h=0}^{N}k^h states, and its inverse limit reconstructs exactly the live finite stacks and failure. A word of length rr induces a natural graded map from level N+rN+r to level NN; a same-level action by a closer is impossible in general.TheoremProved and internally auditedEvidence and limits →Automata and formal languagesGeneralized-Dyck residual dynamicsFinite shadows and reconstructionFPRD-D18; FPRD-T34FPRD Dyck-residual and finite-observation proof recordsReviewed 2026-08-25No documented external or specialist review of this FPRD result is recorded.Publish a diagram of the bonding maps and one explicit failure of same-level closer action.
FPRD-T49For Lf={anbaf(n):n≥0}L_f=\{a^n b a^{f(n)}:n\ge0\}, where f:N→Nf:\mathbb N\to\mathbb N is strictly increasing, the first appearances of every active singleton row, pre-marker row, and empty row give exact formulas for the prefix/future rectangle (G_f(M,N)) and access radius (a_f(N)). A fixed scalar quotient history through horizon (N) can coexist with arbitrarily large access at that same horizon.TheoremProved and internally auditedEvidence and limits →Automata and formal languagesFormal languages and automataSparse-marker accessFPRD-T48; FPRD-T47FPRD proofs on residual access and controlled-Dyck presentationsReviewed 2026-08-26No documented external or specialist review of this FPRD result is recorded.Classify which finite-presentation families constrain the jump term that controls access.
FPRD-T50For a finite controller (M) intersected with a generalized-Dyck language, shortest balanced-controller distances determine exact raw-coordinate arrivals. Minimizing those arrivals inside each bounded semantic row and then maximizing computes (a_{L_M}(N)). If (B_M) is the largest finite balanced distance from an underlying-DFA-reachable source, then aLM(N)≤max⁡{1,(N+1)BM+N}a_{L_M}(N)\le\max\{1,(N+1)B_M+N\}; the class-wide bound is pointwise optimal.Theorem and algorithmProved and internally auditedEvidence and limits →Automata and formal languagesFormal languages and automataControlled-Dyck access calculusFPRD-D24; FPRD-T40; FPRD-T44; FPRD-T49FPRD proofs on residual access and controlled-Dyck presentationsReviewed 2026-08-26No documented external or specialist review of this FPRD result is recorded.Compare the presentation certificate with established visibly-pushdown and weighted shortest-witness formulations.
FPRD-T51For generalized-Dyck words whose stack height reaches at least r≥1r\ge1, qk,r≥(N)=1+∑h=0Nkh+∑h=max⁡(0,2r−N)r−1khq_{k,r}^{\ge}(N)=1+\sum_{h=0}^{N}k^h+\sum_{h=\max(0,2r-N)}^{r-1}k^h and ak,r≥(N)=max⁡(2r,N)a_{k,r}^{\ge}(N)=\max(2r,N). For words staying below (r), qk,r<(N)=1+∑h=0min⁡(N,r−1)khq_{k,r}^{<}(N)=1+\sum_{h=0}^{\min(N,r-1)}k^h and ak,r<(N)=max⁡(1,min⁡(N,r−1))a_{k,r}^{<}(N)=\max(1,\min(N,r-1)).TheoremProved and internally auditedEvidence and limits →Automata and formal languagesFormal languages and automataDepth-threshold profilesFPRD-D24; FPRD-T40; FPRD-T50FPRD proofs on residual access and controlled-Dyck presentationsReviewed 2026-08-26No documented external or specialist review of this FPRD result is recorded.Use the threshold families as calibrations when comparing access certificates across equivalent controllers.
FPRD-T52Only controller states that actually begin balanced segments of legal prefixes are needed in the replacement proof. Their entry balanced diameter cannot increase under a surjective reachable DFA morphism. Minimizing this diameter over regular controllers with the same trace on a fixed Dyck language defines βD(L)\beta_D(L) and gives aL(N)≤max⁡{1,(N+1)βD(L)+N}a_L(N)\le\max\{1,(N+1)\beta_D(L)+N\}.TheoremProved and internally auditedEvidence and limits →Automata and formal languagesFormal languages and automataDyck-trace minimaxFPRD-D25; FPRD-T40; FPRD-T50FPRD proofs on residual access and controlled-Dyck presentationsReviewed 2026-08-26No documented external or specialist review of this FPRD result is recorded.Investigate computable subclasses of the trace-class minimization problem and dependence on the chosen Dyck envelope.
FPRD-T53For a controlled-Dyck language, entry-context residual access ηD\eta_D, top-level balanced residual access γD\gamma_D, and first balanced acceptance flip τD\tau_D satisfy βD≥ηD≥γD≥τD\beta_D\ge\eta_D\ge\gamma_D\ge\tau_D. The value ηD\eta_D is exactly computable by finite completion-summary saturation. Together with any minimized presentation it yields a finite minimax sandwich; endpoint equality certifies optimality. The defect σD=βD−ηD\sigma_D=\beta_D-\eta_D is nonnegative and limit-computable from above, and zero is semidecidable.Theorem and exact finite procedureProved and internally auditedEvidence and limits →Automata and formal languagesFormal languages and automataSemantic access hierarchyFPRD-D25; FPRD-T51; FPRD-T52FPRD proofs on residual access and controlled-Dyck presentationsReviewed 2026-08-26No documented external or specialist review of this FPRD result is recorded.Find either a positive sewing-defect example or a proof that every controlled-Dyck trace has zero defect.
FPRD-T54Let (K_3) contain epsilon and the nonempty one-bracket Dyck words whose terminal run of closing brackets has length 2 mod 32\bmod 3. Its semantic entry access and trace-minimax entry cost agree: ηD(K3)=βD(K3)=4\eta_D(K_3)=\beta_D(K_3)=4. Hence its sewing defect is zero.Theorem and exact exampleProved; finite-state lower bound is computer-assisted and internally auditedEvidence and limits →Automata and formal languagesFormal languages and automataTerminal-descent tradeoffFPRD-D26; FPRD-T53FPRD proofs on residual access and controlled-Dyck presentationsReviewed 2026-08-26No documented external or specialist review of this FPRD result is recorded.Determine whether any controlled-Dyck trace has positive sewing defect.
FPRD-T55The minimum controller size for K3K_3 is three, while the minimum size among presentations with legal-entry diameter at most four is six. Its exact nondominated state/access pairs are therefore (3,6)(3,6) and (6,4)(6,4).Theorem and exact finite-state classificationProved; the five-state exclusion is computer-assisted and internally auditedEvidence and limits →Automata and formal languagesFormal languages and automataModulus-three frontierFPRD-D26; FPRD-T54FPRD proofs on residual access and controlled-Dyck presentationsReviewed 2026-08-26No documented external or specialist review of this FPRD result is recorded.Produce a portable unsatisfiability certificate if the finite-state encoding is revisited.
FPRD-T56The modulus-two trace K2K_2 satisfies ηD(K2)=βD(K2)=4\eta_D(K_2)=\beta_D(K_2)=4. Its natural two-state controller attains that cost, so the single nondominated state/access pair is (2,4)(2,4).Theorem and exact finite-state classificationProved and internally auditedEvidence and limits →Automata and formal languagesFormal languages and automataModulus-two frontierFPRD-D27; FPRD-T53FPRD proofs on residual access and controlled-Dyck presentationsReviewed 2026-08-26No documented external or specialist review of this FPRD result is recorded.Use the exceptional top-level residual at modulus two as a boundary test for broader terminal-descent constructions.
FPRD-T57The modulus-four trace K4K_4 satisfies ηD(K4)=βD(K4)=6\eta_D(K_4)=\beta_D(K_4)=6. Its natural state-minimal four-state controller has cost eight; an explicit six-state controller has cost six; and no controller with at most five states attains cost six. The exact frontier is (4,8)(4,8) and (6,6)(6,6).Theorem and exact finite-state classificationProved; the five-state exclusion is computer-assisted and internally auditedEvidence and limits →Automata and formal languagesFormal languages and automataModulus-four frontierFPRD-D27; FPRD-T55FPRD proofs on residual access and controlled-Dyck presentationsReviewed 2026-08-26No documented external or specialist review of this FPRD result is recorded.Seek a checkable certificate for the five-state exclusion and avoid extrapolating an unproved minimum-state law.
FPRD-T58For terminal-descent traces, ηD(K2)=βD(K2)=4\eta_D(K_2)=\beta_D(K_2)=4, while for every m≥3m\ge3, ηD(Km)=βD(Km)=2(m−1)\eta_D(K_m)=\beta_D(K_m)=2(m-1). A uniform 2m2m-state height-residue/obligation controller attains the semantic lower bound for every modulus.Theorem and uniform constructionProved and internally auditedEvidence and limits →Automata and formal languagesFormal languages and automataAll-modulus theoremFPRD-D27; FPRD-T53FPRD proofs on residual access and controlled-Dyck presentationsReviewed 2026-08-26No documented external or specialist review of this FPRD result is recorded.Determine the minimum number of states needed to attain optimal access beyond moduli two, three, and four.
FPRD-T59For every even modulus mm, an (m+2)(m+2)-state positional controller has Dyck trace KmK_m and entry cost βD(Km)\beta_D(K_m). At m=4m=4 it is isomorphic to the explicit six-state controller in FPRD-T57.Theorem and uniform constructionProved and internally auditedEvidence and limits →Automata and formal languagesFormal languages and automataEven-modulus constructionFPRD-D27; FPRD-T58FPRD proofs on residual access and controlled-Dyck presentationsReviewed 2026-08-26No documented external or specialist review of this FPRD result is recorded.Determine whether m+2 is minimal at optimal cost for any even modulus beyond four.
FPRD-D33A forgotten-action frontier machine has a finite transition list (q,a,X,q′,γ)(q,a,X,q',\gamma), an explicit initial configuration, and final-state acceptance. Each transition consumes one input symbol and replaces the leftmost stack symbol (X) by γ\gamma; there are no epsilon or endmarker steps. Its frontier component (S_u(q)) contains exactly the stacks reachable in control state (q) after the observed prefix (u).Definition and executable machine modelDefined self-containedly and used by the checked recurrenceEvidence and limits →Automata and formal languagesPushdown frontiers and visible projectionsMachine and frontierNo recorded dependenciesFPRD pushdown-frontier proof and formalization recordsReviewed 2026-08-26No documented external or specialist review of this FPRD exposition is recorded.Use this fixed interface when comparing stationary frontier representations; do not conflate it with a PEG or scaffold.
FPRD-T91For every finite alphabet Σ\Sigma, a language L⊆Σ∗L\subseteq\Sigma^* is context-free exactly when L=π(A)L=\pi(A) for a visibly pushdown language A⊆(Σ×{c,r,l})∗A\subseteq(\Sigma\times\{\mathsf c,\mathsf r,\mathsf l\})^*, where π\pi forgets the action tag. The projection is letter-to-letter and length preserving, and (A) may be recognized by a deterministic visibly pushdown automaton.Source theorem and elementary converseSource-verified and reconstructed; not mechanically checkedEvidence and limits →Automata and formal languagesPushdown frontiers and visible projectionsVisible-projection theoremAlur–Madhusudan Proposition 1 and Theorem 2; Closure of context-free languages under homomorphismFPRD pushdown-frontier proof and formalization recordsReviewed 2026-08-26The forward construction and determinization are published results of Alur and Madhusudan; the FPRD application has no documented specialist review.Add a direct theorem-level primary-source locator to the public bibliography and seek a specialist check of the normalization conventions.
FPRD-T92For a forgotten-action frontier machine, (S_{ua}(q')) is the union of γ(X−1Su(q))\gamma(X^{-1}S_u(q)) over transitions (q,a,X,q′,γ)(q,a,X,q',\gamma). A word is accepted exactly when some final control state has a nonempty frontier component. Both identities hold from the initial frontier, including at the empty word.Theorem with Lean verificationMechanically checked and internally auditedEvidence and limits →Automata and formal languagesPushdown frontiers and visible projectionsFrontier recurrence and readoutFPRD-D33FPRD pushdown-frontier proof and formalization recordsReviewed 2026-08-26No documented external or specialist review of this FPRD exposition is recorded.Use the recurrence as the exact semantic target for proposed finite or persistent frontier representations.
FPRD-T93Let K0⊆K1⊆⋯\mathcal K_0\subseteq\mathcal K_1\subseteq\cdots be finite families of canonically normalized scaffolding automata whose union contains every finite scaffold source, with the index bounding all finite source data. If (e_L(N)) is the least (k) for which a member of Kk\mathcal K_k agrees with (L^R) through length (N), then L∈PELL\in\mathsf{PEL} exactly when sup⁡NeL(N)<∞\sup_N e_L(N)<\infty.Theorem and finite pigeonhole argumentProved and internally auditedEvidence and limits →Automata and formal languagesPushdown frontiers and visible projectionsFinite-core sewingLoff–Moreira–Reis Theorem 16FPRD pushdown-frontier proof and formalization recordsReviewed 2026-08-26No documented external or specialist review of this FPRD exposition is recorded.Apply the criterion only to finite normalized strata; test whether projected visible frontiers escape every fixed stratum.
FPRD-T94Suppose a fixed synchronous multistack executor represents a forgotten-action frontier through a fixed derivative basis and fixed slots, with exact initialization, a preserved validity invariant, exact one-letter updates, and exact final-state readout. Then after every word its represented relation equals the pushdown frontier. The executor and its compiled scaffold therefore recognize exactly the source language, including at the empty word.Conditional compilation theorem with Lean verificationMechanically checked and internally auditedEvidence and limits →Automata and formal languagesPushdown frontiers and visible projectionsStationary-cover transferFPRD-T89; FPRD-T92FPRD pushdown-frontier proof and formalization recordsReviewed 2026-08-26No documented external or specialist review of this FPRD exposition is recorded.Construct a stationary bounded-slot cover for broader projected frontiers, or prove a representation-independent resource obstruction.
FPRD-T161Let a scaffolding automaton have tuple (d,k,g,q) with k>=1, put D=sum_(i=1)^k d^i, and m=ceil(log_2(1+gq)). It has an equivalent tuple (D+m,2,1,2). Shortcut ports expose every source endpoint in one hop, and marker ports encode each ordinary source label-control pair as local SELF/missing geometry. The zero marker code is reserved for the distinguished base node. Hence Tr(L) is nonempty exactly when it contains some tuple (D,2,1,2).Theorem · structural normal form and one-dimensional existence criterionSelf-contained constructive proof with combined compiler and structural-code auditsEvidence and limits →Automata and formal languagesReplayable memory and cut responsesStructural scaffold normal-form theoremFPRD-T160; FPRD-T157; Loff--Moreira--Reis scaffolding automataStructural normal form for scaffolding automataReviewed 2026-09-23A targeted literature search found the original scaffold model but no published unary-label, two-control structural normal form; no specialist review or priority claim is recorded.Study the minimum canonical structural degree delta_str(L), including composition laws and lower bounds that survive every finite label and control encoding.
FPRD-T160If a scaffolding automaton has tuple (d,k,g,q) with k>=2, then it has an equivalent tuple (sum_(i=1)^k d^i,2,g,q). The compiler gives each physical node one shortcut port for every original port word of length at most k. The compiled radius-two view reconstructs the original radius-k view, distinguishing base from missing at shortcut endpoints; at most two hops install every shortcut on the next node. Hence SA_<=2=SA. Combined with FPRD-T159, SA_<=1=REG is a strict subset of SA_<=2=SA.Theorem · complete distance normalization for scaffolding automataSelf-contained constructive proof with machine, symbolic-descriptor, and strictness auditsEvidence and limits →Automata and formal languagesReplayable memory and cut responsesDistance-two normal-form theoremFPRD-T159; Loff--Moreira--Reis scaffolding automataDistance-two normal form for scaffolding automataReviewed 2026-09-23A targeted literature search found the original scaffold model but no published distance-two normalization; no specialist review or priority claim is recorded.Replace distance-based expressiveness questions with degree-versus-distance succinctness bounds and seek lower bounds against the entire distance-two normal form.
FPRD-T159Every distance-one scaffolding automaton of degree d, working-alphabet size g, and q controls compiles to a DFA with at most N=q[1+(g+1)^(d+1)] states, so its residual tower stabilizes by horizon N-1. Conversely, every regular language has a distance-one scaffold presentation. Hence SA_<=1=REG. The explicit degree-two, distance-two persistent selector is nonregular, so REG=SA_<=1 is a strict subset of SA_<=2.Theorem · exact base tier and strict first step of the scaffold distance hierarchySelf-contained constructive proof with compiler and strictness auditsEvidence and limits →Automata and formal languagesReplayable memory and cut responsesDistance-one collapse theoremFPRD-T153; FPRD-T151; Loff--Moreira--Reis scaffolding automataDistance-one scaffolds collapse to finite automataReviewed 2026-09-23A targeted literature search found the original scaffold model but no published statement of this distance-one characterization; no specialist review or priority claim is recorded.Use T160's complete distance normalization to study degree-versus-distance succinctness and optimal degree rather than further expressiveness levels.
FPRD-T158Let (d,k,g,q) lie in Tr(L), let U be a nonempty finite set of fixed suffixes, and let b be any Boolean function of their membership answers. With R_(k,h)=0 for h=0 or k=0 and R_(k,h)=k+(h-1)(k-1) otherwise, put D_U=max over u in U of R_(k,|u|+1). Then the observer language {p : b((1_L(pu))_(u in U))=1} has transport tuple (d,D_U,g,q 2^|U|). The compiled machine uses exactly the original persistent graph. In particular, every fixed right quotient L/u preserves nonempty stationary transport spectrum.Theorem · finite-observer closure with explicit transport boundsSelf-contained proof with compiled-control, locality, and sharpness auditsEvidence and limits →Automata and formal languagesReplayable memory and cut responsesFinite future-observer theoremFPRD-T153; FPRD-D45Finite future observers internalize into stationary transportReviewed 2026-09-23The proof uses the locally established readable-cone theorem FPRD-T153; no external or specialist review of this resource-bound formulation is recorded.Define and test observer families whose suffix sets grow with the cut, since every fixed finite right-context observer is now known to compile.
FPRD-D45The stationary transport spectrum Tr(L) is the set of resource ceilings (degree, descriptor distance, working-alphabet size, control-state count) under which the canonical residual dynamics of L has a one-node-per-symbol bounded-locality persistent presentation. It minimizes over all presentations within the scaffolding model.Definition · implementation-minimized stationary transport invariantDefined exactly at the finite scaffolding-automaton boundaryEvidence and limits →Automata and formal languagesReplayable memory and cut responsesStationary transport spectrumFPRD-T156; Loff--Moreira--Reis scaffolding automataStationary transport spectraReviewed 2026-09-23No documented external or specialist review of this FPRD result is recorded.Place positive forgotten-action tiers inside explicit spectrum cones and search for presentation-independent emptiness criteria.
FPRD-T157For every language L, Tr(L) is upward closed in the componentwise order and therefore, by Dickson's lemma, is generated by a unique finite antichain of Pareto-minimal resource tuples whenever nonempty. Complement preserves Tr exactly. If tuples (d_i,k_i,g_i,q_i) present L_i, then every binary Boolean combination has a presentation bounded by (d_1+d_2, max(k_1,k_2), g_1g_2, q_1q_2). Nonempty spectrum is equivalent to recognition by a finite scaffolding automaton and implies a PEG for the reverse language through FPRD-T110.Theorem · finite basis and Boolean calculus for transport resourcesSelf-contained proof with finite-basis and paired-machine auditsEvidence and limits →Automata and formal languagesReplayable memory and cut responsesFinite Pareto basis theoremFPRD-D45; Dickson's lemma; FPRD-T110Stationary transport spectraReviewed 2026-09-23The finite-basis step is classical Dickson's lemma and the model is due to Loff, Moreira, and Reis; no external review of this FPRD spectrum formulation is recorded.Develop lower bounds that exclude all Pareto tuples simultaneously, or compile projected frontier representations into an explicit feasible tuple.
FPRD-D44For a language L, Q_h is the finite set of response rows of prefixes on continuations of length at most h. Restriction gives surjections Q_(h+1) to Q_h, forming an inverse system. Reading one input symbol maps Q_(h+1) to Q_h by selecting the corresponding response subtree.Definition · canonical finite-horizon quotient systemDefined self-containedly and connected to residual derivativesEvidence and limits →Automata and formal languagesReplayable memory and cut responsesResidual towerFPRD-D42; left quotients; inverse systems of finite setsResidual towers and canonical transportReviewed 2026-09-23No documented external or specialist review of this FPRD result is recorded.Use the inverse-limit shift as the semantic object for an encoding-independent theory of stationary transport presentations.
FPRD-T156The inverse limit of the finite-horizon residual tower is a compact totally disconnected deterministic response machine with continuous input transitions. The full Myhill--Nerode residual space embeds equivariantly and densely. A language is regular exactly when the tower stabilizes, equivalently when its quotient sizes are bounded or one restriction map Q_(h+1) to Q_h is bijective.Theorem · canonical residual completion and stabilization criterionSelf-contained proof with exhaustive finite auditEvidence and limits →Automata and formal languagesReplayable memory and cut responsesResidual completion theoremFPRD-D44; Myhill--Nerode theorem; inverse limits of finite setsResidual towers and canonical transportReviewed 2026-09-23The theorem is aligned with established profinite and topological recognition theory; no external review of this FPRD formulation is recorded.Use the stationary framework D45/T157 and later compilation results; the remaining frontier is structural lower bounds, spectrum emptiness, or explicit compilation for consequential presentations.
FPRD-D43For a demanded map on a finite product source, operational support records coordinates touched by a replay trace, semantic support records coordinates capable of changing the demanded answer, and quotient memory identifies sources with equal complete answers. These are distinct resources.Definition · three-layer replayable-memory modelDefined self-containedly with exact comparison mapsEvidence and limits →Automata and formal languagesReplayable memory and cut responsesThree memory layersFPRD-T150; FPRD-D42The support-quotient theorem for replayable memoryReviewed 2026-09-23No documented external or specialist review of this FPRD result is recorded.Define stationary transport cost for updating and naming quotient classes as the cut advances.
FPRD-T155For a map F on a finite product source, the essential-coordinate set E(F) is the unique least sufficient coordinate support; the minimum exact deterministic summary has |F(X)| states; and |F(X)| is at most the product of the alphabets on E(F), with equality exactly when the induced map is injective. For a family of futures, essential support is the union of component supports. Every stable adaptive replay envelope contains E(F).Theorem · exact support-quotient factorizationSelf-contained proof with exhaustive finite auditEvidence and limits →Automata and formal languagesReplayable memory and cut responsesSupport-quotient theoremFPRD-D43; FPRD-T150; FPRD-T152The support-quotient theorem for replayable memoryReviewed 2026-09-23No documented external or specialist review of this FPRD result is recorded.Use D45/T157 and the later normal-form and selector results to study the surviving structural cost of stationary transport across cuts.
FPRD-D42A finite cut-response system records the answer beta(p,c) for each past p and possible continuation c. Its response dimension is log2 of the number of distinct response rows, separating the information needed for readiness across a continuation family from the replay support used by any one completed continuation.Definition · finite-cut communication invariantDefined self-containedly and connected exactly to residual rowsEvidence and limits →Automata and formal languagesReplayable memory and cut responsesCut-response definitionFPRD-D41; deterministic one-way communicationCut-response factorization and linear observer dimensionReviewed 2026-09-23No documented external or specialist review of this FPRD result is recorded.Extend the finite-horizon scaffold capacity bound to richer stationary frontier presentations.
FPRD-T152For every finite cut-response system, the minimum number of exact deterministic summary states equals the number of distinct response rows. Hence the fixed-length one-way cost is ceil(log2 R) bits for R rows. For linear observers a·x over F_q^n whose span has dimension r, the exact minimum is q^r states, or ceil(r log2 q) bits. Any resource class with at most B(s) cut presentations can realize the system only if R<=B(s).Theorem · exact cut factorization and capacity transferSelf-contained proof and exhaustive finite falsification auditEvidence and limits →Automata and formal languagesReplayable memory and cut responsesCut-response factorizationFPRD-D42; deterministic one-way communication; rank-nullityCut-response factorization and linear observer dimensionReviewed 2026-09-23No documented external or specialist review of this FPRD result is recorded.Use FPRD-T154 to replace row cardinality by a structural response invariant or a tighter reachable-presentation capacity theorem.
FPRD-T153Fix a Loff--Moreira--Reis scaffolding automaton of degree d, distance k, working alphabet size g, and control set Q. For continuation horizon h, every response row is determined by the cut control state and the radius R=k+(h-1)(k-1) unfolded neighbourhood when k,h>=1, with radius zero when k=0 or h=0. If V_0=g+1 and V_(r+1)=1+(g+1)V_r^d, then every horizon-h cut has at most |Q|V_R distinct response rows. The radius R is uniformly sharp.Theorem · readable-cone capacity and sharp horizon radiusSelf-contained proof with exhaustive finite structural auditEvidence and limits →Automata and formal languagesReplayable memory and cut responsesFinite-horizon scaffold capacityFPRD-T152; FPRD-T133; Loff--Moreira--Reis scaffolding automataFinite-horizon response capacity of scaffolding automataReviewed 2026-09-23No documented external or specialist review of this FPRD result is recorded.Use FPRD-T154 to replace raw row cardinality by a structural invariant that survives larger fixed scaffold parameters.
FPRD-T154For every finite input alphabet of size s, one fixed generic T153 parameter tuple, degree max(2,s), distance 2, one working label, and one control state, has a numerical abstract-view envelope at least as large as the maximum possible number of Boolean response rows over every continuation horizon h. Therefore a lower-bound proof using only finite-horizon response-row cardinality cannot exceed every T153 envelope and cannot by itself separate a language from all scaffolding automata. Any PEG transfer must account for reversal.Theorem · parameter-uniform barrier for a cardinality methodSelf-contained elementary proof with exact and symbolic finite auditEvidence and limits →Automata and formal languagesReplayable memory and cut responsesUniversal row-count barrierFPRD-T152; FPRD-T153; finite Boolean response tablesThe universal row-count barrierReviewed 2026-09-23No documented external or specialist review of this FPRD result is recorded.Define a cut invariant that records advance compatibility, horizon coherence, or realizability structure rather than only the number of rows.
FPRD-D41For a fixed family of continuations, a prefix's continuation-exposed replay profile records the accept/reject response to each continuation. Pointwise replay width is the largest source slice used by one completed continuation, while the future-exposed union contains every old source coordinate selected across the family.Definition · bridge from execution slices to residual observationsDefined self-containedly and calibrated on an exact selector familyEvidence and limits →Automata and formal languagesReplayable memory and cut responsesReplay-profile definitionFPRD-D40; FPRD-T150Replay fan-out theoremReviewed 2026-09-23No documented external or specialist review of this FPRD result is recorded.Define transport orbits for persistent roots and test them against a visible lift of the Kim-Park SCA-hard language C.
FPRD-T151Let M contain the nonempty binary words whose middle symbol, at one-based position ceil(n/2), is 1. Every completed word has a one-source-cell replay certificate when length is public shape data. Nevertheless, for every r there are 2^r prefixes of length 2r and r continuations whose response profiles are all distinct. Thus M has at least 2^r residuals at that cut, and every exact deterministic one-pass recognizer needs at least 2^r configurations there.Theorem · replay-width/residual-fan-out separationSelf-contained elementary proof and exhaustive finite auditEvidence and limits →Automata and formal languagesReplayable memory and cut responsesReplay fan-out separationFPRD-D41; FPRD-T150; Myhill--Nerode residual separationReplay fan-out theoremReviewed 2026-09-23No documented external or specialist review of this FPRD result is recorded.Use the explicit degree-two unary-query selector as a positive calibration, then study branching and merging demand families rather than a single backwards cursor.
FPRD-SH-D01For a letter-labelled NFA AA and state qq, the loop spectrum is ΛA(q)={σ:q→σq}\Lambda_A(q)=\{\sigma:q\xrightarrow{\sigma}q\}.Definition · local quotient invariantPrecisely stated and used by the obstruction theoremEvidence and limits →Automata and formal languagesPrefix quotients under shuffleLoop spectrum and quotient conventionNo recorded dependenciesFPRD Lab definition applied to Broda et al., “Location based automata for expressions with shuffle and intersection” (2023)Reviewed 2026-09-01No documented external or specialist review of these FPRD results is recorded.Use the stronger incoming-spectrum invariant FPRD-SH-T04 for non-recurrent shuffle failures.
FPRD-SH-L01For every regular expression with shuffle, every noninitial state of its prefix automaton has one incoming transition label; hence no prefix state has self-loops on two distinct letters.Lemma · structural propertySelf-contained proof at the stated constructionEvidence and limits →Automata and formal languagesPrefix quotients under shuffleHomogeneity proofBroda et al., “Location based automata for expressions with shuffle and intersection” (2023), Section 6Broda, Machiavelo, Moreira, and Reis, “Location based automata for expressions with shuffle and intersection” (2023); FPRD reconstructionReviewed 2026-09-01No documented external or specialist review of these FPRD results is recorded.Retain homogeneity as the target-side invariant in generated quotient tests.
FPRD-SH-T01For every existential state quotient π:A↠B\pi:A\twoheadrightarrow B, ΛA(q)⊆ΛB(π(q))\Lambda_A(q)\subseteq\Lambda_B(\pi(q)) for every state qq.Theorem · elementary quotient invariantSelf-contained proofEvidence and limits →Automata and formal languagesPrefix quotients under shuffleLoop-spectrum monotonicity proofFPRD-SH-D01Elementary labelled-graph fact; FPRD application to the shuffle/prefix seamReviewed 2026-08-31No documented external or specialist review of these FPRD results is recorded.Use the invariant as a constant-time rejection test before exhaustive quotient search.
FPRD-SH-T02Let α=β⨿γ\alpha=\beta\amalg\gamma. In the full asynchronous-product location automaton, if the two components have recurrent locations with self-loops on distinct letters a≠ba\ne b, then APre(α)A_{\mathrm{Pre}}(\alpha) is not an existential state quotient of APOS(α)A_{\mathrm{POS}}(\alpha). For a construction that trims unreachable locations, the paired product location must be reachable.Theorem · infinite obstruction familySelf-contained proof; exact small-case verificationEvidence and limits →Automata and formal languagesPrefix quotients under shuffleIndependent-recurrence theorem and proofFPRD-SH-L01; FPRD-SH-T01; Broda et al., “Location based automata for expressions with shuffle and intersection” (2023)FPRD Lab analysis of the shuffle location construction in Broda et al. (2023)Reviewed 2026-09-01No documented external or specialist review of these FPRD results is recorded.Treat this loop theorem as a special case of the exact incoming-spectrum classification FPRD-SH-T05.
FPRD-SH-X01For distinct letters a≠ba\ne b, the three-state prefix automaton of a∗⨿b∗a^*\amalg b^* is not a quotient of its four-state location automaton. The expression has exactly two letter occurrences, the minimum among shuffle expressions whose two operands both contain a letter.Counterexample · sharp size boundSelf-contained proof and exact verifier reproductionEvidence and limits →Automata and formal languagesPrefix quotients under shuffleMinimal counterexample and transition tablesFPRD-SH-T02FPRD deduction; Broda et al. (2023), Example 13, supplies the four-occurrence comparisonReviewed 2026-09-01No documented external or specialist review of these FPRD results is recorded.Retain as the sharp occurrence-count boundary; make no literature-priority claim.
FPRD-SH-X02For a∗⨿a∗a^*\amalg a^*, merging the three noninitial location states gives the two-state prefix automaton as an ordinary existential quotient, but no such quotient partition is left-invariant.Counterexample · sharp boundaryExact proof and exhaustive partition checkEvidence and limits →Automata and formal languagesPrefix quotients under shuffleUnary control and predecessor defectFPRD-SH-T03FPRD Lab deduction using the 2023 shuffle location/prefix constructionsReviewed 2026-09-01No documented external or specialist review of these FPRD results is recorded.Retain this as the smallest exceptional case in the all-length proof FPRD-SH-T06.
FPRD-SH-T03A state partition π\pi is left-invariant exactly when initiality is saturated and every pair q,q′q,q' in one block has identical predecessor-block sets {π(r):r→σq}\{\pi(r):r\xrightarrow{\sigma}q\} for every letter σ\sigma.Theorem · exact criterionSelf-contained reformulation of the standard definitionEvidence and limits →Automata and formal languagesPrefix quotients under shufflePredecessor criterionLeft invariance on the reversed automaton2019 left-quotient architecture; FPRD predecessor-profile reformulationReviewed 2026-09-01No documented external or specialist review of these FPRD results is recorded.Combine this criterion with Boolean block equations for larger SAT-checkable quotient certificates.
FPRD-SH-C01For ((ab)∗)⨿((bc)∗)((ab)^*)\amalg((bc)^*), exact reconstruction gives a 9-state, 18-transition location automaton, a 9-state marked prefix automaton, and an 8-state, 16-transition unmarked prefix automaton; exhaustive partition search finds no quotient.Computational finding · source reproductionIndependently reproduced with an exact structural checkerEvidence and limits →Automata and formal languagesPrefix quotients under shufflePublished example reconstructionBroda et al., “Location based automata for expressions with shuffle and intersection” (2023), Section 6Broda, Machiavelo, Moreira, and Reis, “Location based automata for expressions with shuffle and intersection” (2023), Example 13Reviewed 2026-09-01No documented external or specialist review of these FPRD results is recorded.Use the incoming-spectrum witness from FPRD-SH-T04 as the direct explanation of this example.
FPRD-SH-C02Among all 306 expressions x∗⨿y∗x^*\amalg y^* over {a,b,c}\{a,b,c\} with ∣x∣+∣y∣≤4|x|+|y|\le4, 288 have no ordinary prefix quotient; the 18 ordinary-quotient cases are all unary same-letter controls, and none has a left-invariant quotient.Computational finding · bounded censusExhaustive within the stated finite domain; its pattern is now proved by FPRD-SH-T05Evidence and limits →Automata and formal languagesPrefix quotients under shuffleCensus table and scopeExact automaton constructor; Exhaustive set-partition searchFPRD Lab bounded starred-word shuffle censusReviewed 2026-08-31No documented external or specialist review of these FPRD results is recorded.Retain this census as the discovery record and finite cross-check for FPRD-SH-T05.
FPRD-SH-T04For a letter-labelled NFA AA, let IA(q)={σ:∃p  (p→σq)}I_A(q)=\{\sigma:\exists p\;(p\xrightarrow{\sigma}q)\}. If π:A↠B\pi:A\twoheadrightarrow B is an existential state quotient, then IA(q)⊆IB(π(q))I_A(q)\subseteq I_B(\pi(q)) for every state qq.Theorem · local quotient invariantSelf-contained proof; strictly strengthens the loop-spectrum testEvidence and limits →Automata and formal languagesPrefix quotients under shuffleIncoming-spectrum theoremExistential block-transition conventionElementary labelled-graph fact; FPRD application to shuffle locationsReviewed 2026-08-31No documented external or specialist review of these FPRD results is recorded.Test the invariant on broader non-starred shuffle syntax.
FPRD-SH-T05For nonempty words x,yx,y, APre(x∗⨿y∗)A_{\mathrm{Pre}}(x^*\amalg y^*) is an existential state quotient of APOS(x∗⨿y∗)A_{\mathrm{POS}}(x^*\amalg y^*) if and only if x=amx=a^m and y=any=a^n for one letter aa and integers m,n≥1m,n\ge1.Theorem · exact classificationSelf-contained proof with a closed-form quotient certificate and executable auditEvidence and limits →Automata and formal languagesPrefix quotients under shuffleExact dichotomy and constructive proofFPRD-SH-L01; FPRD-SH-T04; Broda et al., “Location based automata for expressions with shuffle and intersection” (2023)FPRD Lab classification using the shuffle location/prefix constructions of Broda et al. (2023)Reviewed 2026-09-01No documented external or specialist review of these FPRD results is recorded.Use FPRD-SH-T06 for the stronger left-invariant classification.
FPRD-SH-T06For all nonempty words x,yx,y, APre(x∗⨿y∗)A_{\mathrm{Pre}}(x^*\amalg y^*) is not a left-invariant quotient of APOS(x∗⨿y∗)A_{\mathrm{POS}}(x^*\amalg y^*).Theorem · exact classificationSelf-contained all-length proof with exact boundary and parameter auditsEvidence and limits →Automata and formal languagesPrefix quotients under shuffleComplete left-quotient obstructionFPRD-SH-T03; FPRD-SH-T05; Broda et al., “Location based automata for expressions with shuffle and intersection” (2023)FPRD Lab deduction using the shuffle location/prefix constructions of Broda et al. (2023)Reviewed 2026-09-01No documented external or specialist review of these FPRD results is recorded.Test whether an analogous predecessor obstruction classifies broader non-starred shuffle syntax.
FPRD-SH-C03For 1≤m,n≤161\le m,n\le16 at the audited parameter pairs, the closed-form projection for (am)∗⨿(an)∗(a^m)^*\amalg(a^n)^* produces an NFA exactly equal to the recursively constructed prefix automaton; the largest audit maps 289 states to 257.Computational finding · theorem auditExact equality checks pass at all nine selected parameter pairsEvidence and limits →Automata and formal languagesPrefix quotients under shuffleExecutable auditFPRD-SH-T05; Exact automaton constructorFPRD Lab parameterized certificate verifierReviewed 2026-09-01No documented external or specialist review of these FPRD results is recorded.Keep the finite audit synchronized with any proof or implementation revision.
FPRD-SH-D02For strong synchronization, solo terminal events are allowed only outside Γ\Gamma and paired terminal events only on equal letters in Γ\Gamma; for arbitrary synchronization the same paired clause is added without suppressing solo events. Applying the usual backward RεR_\varepsilon-recursion to these clauses defines the natural prefix automata studied here.Definition · FPRD extension of the cited location frameworkPrecisely stated for strong and arbitrary synchronization; the weak operator uses a separate backward-memory definitionEvidence and limits →Automata and formal languagesPrefix quotients under shuffleSynchronized prefix conventionBroda et al., “The Prefix Automaton” (2021); Broda et al., “Location automata for synchronised shuffle expressions” (2023)FPRD prefix extension of Broda et al., “The Prefix Automaton” (2021), and Broda et al., “Location automata for synchronised shuffle expressions” (2023)Reviewed 2026-09-01No documented external or specialist review of these FPRD results is recorded.Keep the strong/arbitrary convention separate from the proved weak backward receipt.
FPRD-SH-T07For m,n≥1m,n\ge1, under strong synchronization on Γ={a}\Gamma=\{a\}, the accessible location automaton and the natural prefix automaton of (am)∗⨿sΓ(an)∗(a^m)^*\mathbin{\amalg^{\Gamma}_{s}}(a^n)^* are isomorphic cycles of length lcm⁡(m,n)\operatorname{lcm}(m,n), with their initial state attached. In particular the prefix automaton is a left-invariant quotient of the accessible location automaton.Theorem · exact all-parameter classificationSelf-contained orbit proof with parameterized executable auditEvidence and limits →Automata and formal languagesPrefix quotients under shuffleMandatory-synchronization theoremFPRD-SH-D02; Broda et al., “Location automata for synchronised shuffle expressions” (2023), strong synchronized-shuffle constructionFPRD deduction from the Broda–Machiavelo–Moreira–Reis strong synchronized-shuffle construction (2023)Reviewed 2026-09-01No documented external or specialist review of these FPRD results is recorded.Determine which non-unary strong synchronized families retain the same accessible-orbit quotient.
FPRD-SH-T08For m,n≥1m,n\ge1, under arbitrary synchronization on Γ={a}\Gamma=\{a\}, the natural prefix automaton of (am)∗⨿aΓ(an)∗(a^m)^*\mathbin{\amalg^{\Gamma}_{a}}(a^n)^* is an ordinary existential quotient of its location automaton exactly when min⁡(m,n)=1\min(m,n)=1, and it is a left-invariant quotient exactly when m=n=1m=n=1.Theorem · exact all-parameter classificationSelf-contained necessity and constructive sufficiency proofs with exhaustive boundary auditEvidence and limits →Automata and formal languagesPrefix quotients under shuffleArbitrary-synchronization classificationFPRD-SH-D02; FPRD-SH-T03; Broda et al., “Location automata for synchronised shuffle expressions” (2023), arbitrary synchronized-shuffle constructionFPRD deduction from the Broda–Machiavelo–Moreira–Reis arbitrary synchronized-shuffle construction (2023)Reviewed 2026-09-01No documented external or specialist review of these FPRD results is recorded.Test whether the forced-initial-block obstruction extends to non-unary arbitrary synchronization.
FPRD-SH-B01The published weak synchronized location construction records forward memory Δ,Λ\Delta,\Lambda for solo synchronized letters since the last joint event. A prefix construction based on last events instead needs a dual receipt describing allowable solo synchronized letters until the next joint event; reusing the forward memory does not by itself define that automaton.Boundary · resolved definition gateRequirement discharged by the proved reversal-dual constructionEvidence and limits →Automata and formal languagesPrefix quotients under shuffleWeak-synchronization boundaryBroda et al., “Location automata for synchronised shuffle expressions” (2023), weak synchronized-shuffle construction; Broda et al., “The Prefix Automaton” (2021)FPRD analysis of the directionality mismatch in the cited constructionsReviewed 2026-09-01No documented external or specialist review of these FPRD results is recorded.Retain the directionality distinction when extending the receipt beyond the unary family.
FPRD-SH-D03Define u⋈←Γ,D,Ev={zR:z∈uR⋈Γ,D,EvR}u\overleftarrow{\bowtie}_{\Gamma,D,E}v=\{z^R:z\in u^R\bowtie_{\Gamma,D,E}v^R\}, where the published auxiliary operator on the right records solo synchronized letters since the previous joint event. The reversal-dual parameters record solo letters before the next joint event and give a correct final-event RεR_\varepsilon-recursion for weak synchronized shuffle.Definition theorem · backward-memory constructionSelf-contained reversal proof with exact unary graph auditEvidence and limits →Automata and formal languagesPrefix quotients under shuffleBackward-receipt definition and proofFPRD-SH-B01; Broda et al., “The Prefix Automaton” (2021); Broda et al., “Location automata for synchronised shuffle expressions” (2023), weak synchronized-shuffle operatorFPRD reversal-dual extension of the cited weak synchronized frameworkReviewed 2026-09-01No documented external or specialist review of these FPRD results is recorded.Test whether the receipt remains finite and useful for non-unary or nested weak shuffles.
FPRD-SH-T09For every m,n≥1m,n\ge1, the backward-receipt prefix automaton of (am)∗⨿{a}w(an)∗(a^m)^*\mathbin{\amalg^w_{\{a\}}}(a^n)^* is an existential state quotient of its accessible weak location automaton.Theorem · exact constructive quotientAll-length proof with closed-form quotient and exact parameter auditEvidence and limits →Automata and formal languagesPrefix quotients under shuffleWeak ordinary-quotient theoremFPRD-SH-D03; Broda et al., “Location automata for synchronised shuffle expressions” (2023), weak synchronized-shuffle constructionFPRD deduction from the Broda–Machiavelo–Moreira–Reis weak synchronized-shuffle construction (2023) and the FPRD reversal-dual receiptReviewed 2026-09-01No documented external or specialist review of these FPRD results is recorded.Search for a non-unary family in which the shifted receipt projection remains exact.
FPRD-SH-T10For every m,n≥1m,n\ge1, the backward-receipt prefix automaton of (am)∗⨿{a}w(an)∗(a^m)^*\mathbin{\amalg^w_{\{a\}}}(a^n)^* is not a left-invariant quotient of its weak location automaton.Theorem · exact impossibility classificationAll-length determinization-orbit proof with exceptional-case auditEvidence and limits →Automata and formal languagesPrefix quotients under shuffleWeak left-quotient obstructionFPRD-SH-D03; Determinization preservation under left quotientsFPRD determinization-orbit consequence for the Broda–Machiavelo–Moreira–Reis weak location construction and the FPRD prefix receiptReviewed 2026-09-01No documented external or specialist review of these FPRD results is recorded.Test eventual subset-period mismatch as an obstruction for non-unary synchronized products.
FPRD-SH-C05Exact construction verifies the weak ordinary quotient for 1,024 pairs with 1≤m,n≤321\le m,n\le32, verifies the APOS/APre subset-orbit formulas for 256 pairs with 1≤m,n≤161\le m,n\le16, and exhausts 11,825 compatible partitions across (1,1),(1,2),(2,1)(1,1),(1,2),(2,1).Computational finding · theorem auditAll exact structural, orbit, and boundary checks passEvidence and limits →Automata and formal languagesPrefix quotients under shuffleWeak synchronized auditFPRD-SH-T09; FPRD-SH-T10; Exact automaton constructorFPRD Lab weak-synchronization verifierReviewed 2026-09-01No documented external or specialist review of these FPRD results is recorded.Keep the verifier synchronized with any extension beyond the unary family.
FPRD-SH-C04Exact construction checks 576 strong and 576 arbitrary synchronized pairs for 1≤m,n≤241\le m,n\le24; exhaustive search over 10,534 compatible partitions independently verifies the ordinary- and left-quotient boundary in the six smallest arbitrary-synchronization instances.Computational finding · theorem auditExact structural and exhaustive boundary checks passEvidence and limits →Automata and formal languagesPrefix quotients under shuffleSynchronized threshold auditFPRD-SH-T07; FPRD-SH-T08; Exact automaton constructorFPRD Lab synchronized-shuffle verifierReviewed 2026-09-01No documented external or specialist review of these FPRD results is recorded.Extend the exact checker to a non-unary synchronized family only after its prefix receipt is stated precisely.
FPRD-SH-T11Let ∥ψ\Vert_\psi be an arbitrary-arity memoryless Boolean product of NFAs, and let EiE_i be a left-invariant equivalence on component AiA_i. The coordinatewise product equivalence E=∏iEiE=\prod_iE_i is left-invariant on ∥ψ(A1,…,An)\Vert_\psi(A_1,\ldots,A_n), and ∥ψ(A1,…,An)/E≅∥ψ(A1/E1,…,An/En)\Vert_\psi(A_1,\ldots,A_n)/E\cong\Vert_\psi(A_1/E_1,\ldots,A_n/E_n).Theorem · arbitrary-arity quotient transferSelf-contained predecessor proof with strengthened independent boundary auditEvidence and limits →Automata and formal languagesPrefix quotients under shuffleBoolean-product transfer theoremFPRD-SH-T03; The 2026 Boolean-product automaton constructionBroda–Machiavelo–Moreira–Reis (2026) product construction; FPRD left-handed consequence using the Broda–Holzer–Maia–Moreira–Reis (2019) definition of left invarianceReviewed 2026-09-01No documented external or specialist review of these FPRD results is recorded.Compare the canonical product of component prefix quotients with the natural prefix automaton of one Boolean-product expression.
FPRD-SH-B02For ordinary component expressions, FPRD-SH-T11 gives a canonical left quotient from the Boolean product of their position automata to the Boolean product of their prefix automata. This target need not equal the natural prefix automaton of the combined Boolean-product expression: pure shuffle a∗⨿b∗a^*\amalg b^* is already a counterexample to that identification.Boundary · exact construction separationExact boundary, now explained by the event-signature expansion theoremEvidence and limits →Automata and formal languagesPrefix quotients under shuffleTwo prefix constructionsFPRD-SH-T11; FPRD-SH-X01; The classical position-to-prefix left quotientFPRD comparison of the 2026 Boolean-product automaton with the 2021/2023 prefix constructionsReviewed 2026-09-01No documented external or specialist review of these FPRD results is recorded.Use FPRD-SH-T12 through FPRD-SH-T14 for the exact construction and policy criteria.
FPRD-SH-T12For a flat Boolean-product expression with marked ordinary components, the natural backward prefix automaton is isomorphic to the useful canonical product of the component prefix automata after splitting every noninitial product state qq into one copy for each incoming event signature (a,S)∈Sig⁡(q)(a,S)\in\operatorname{Sig}(q). Hence ∣QPre∣=1+∑q≠q0∣Sig⁡(q)∣|Q_{\mathrm{Pre}}|=1+\sum_{q\ne q_0}|\operatorname{Sig}(q)|.Theorem · exact construction identificationSelf-contained structural proof with exact projection auditEvidence and limits →Automata and formal languagesPrefix quotients under shuffleEvent-signature expansion theoremFPRD-SH-T11; The 2021 prefix recursion; The 2026 Boolean-product support policyFPRD extension of the 2021 prefix and 2026 Boolean-product constructionsReviewed 2026-09-01No documented external or specialist review of these FPRD results is recorded.Compare the event-signature expansion directly with the 2026 paper's Glushkov and follow constructions.
FPRD-SH-T13For a fixed flat Boolean-product expression with marked ordinary components, the natural prefix automaton is isomorphic to the useful canonical component-prefix product if and only if every noninitial useful product state qq has exactly one incoming event signature. If some qq has two signatures, the natural marked automaton is strictly larger and cannot be a quotient of the product.Corollary · expression-specific iff criterionImmediate exact consequence of the event-signature expansionEvidence and limits →Automata and formal languagesPrefix quotients under shuffleUnique-signature criterionFPRD-SH-T12FPRD event-signature analysisReviewed 2026-09-01No documented external or specialist review of these FPRD results is recorded.Use the signature count as the exact state-overhead statistic for algorithmic bounds.
FPRD-SH-T14A memoryless Boolean policy makes the natural prefix automaton isomorphic to the useful canonical component-prefix product for every tuple of ordinary component expressions if and only if every active letter aa has one allowed support SaS_a and Sa∩Sb≠∅S_a\cap S_b\ne\varnothing for every two distinct active letters. In the positive case the quotient is the identity-block quotient; every policy violation has a starred-expression witness whose natural automaton is strictly larger than the product.Theorem · sharp universal policy classificationSelf-contained necessity and sufficiency proof with independent complete small-policy auditEvidence and limits →Automata and formal languagesPrefix quotients under shuffleSignature-rigidity classificationFPRD-SH-T12; FPRD-SH-T13; Homogeneity of component prefix automataFPRD deduction from Broda–Maia–Moreira–Reis (2021) and Broda–Machiavelo–Moreira–Reis (2026)Reviewed 2026-09-01No documented external or specialist review of these FPRD results is recorded.Use FPRD-SH-T15 and FPRD-SH-T16 for the exact local bound and its policy-only complexity boundary.
FPRD-SH-T15Let CψC_\psi have the policy signatures (a,S)(a,S) as vertices, with distinct vertices adjacent exactly when they share a letter or have disjoint supports. Over every tuple of ordinary component expressions, the largest attainable number of incoming signatures at one useful canonical product state is exactly ω(Cψ)\omega(C_\psi). Hence ∣Sig⁡(q)∣≤ω(Cψ)|\operatorname{Sig}(q)|\le\omega(C_\psi) and Δ(E)≤(ω(Cψ)−1)(∣Q(P)∣−1)\Delta(E)\le(\omega(C_\psi)-1)(|Q(P)|-1).Theorem · exact support-graph state-complexity boundSelf-contained upper bound and exact starred realization; finite audit passesEvidence and limits →Automata and formal languagesPrefix quotients under shuffleCompatibility-graph theoremFPRD-SH-T12; Homogeneity of component prefix states; Graph clique numberFPRD support-graph consequence of the Boolean-product event-signature expansionReviewed 2026-09-01No documented external or specialist review of these FPRD results is recorded.Use FPRD-SH-T17 and FPRD-SH-T18 for the exact global collision receipt and disjoint-support count.
FPRD-SH-T16Given an explicitly listed memoryless support policy ψ\psi and kk, deciding whether some tuple of ordinary component expressions can produce one useful canonical product state with at least kk incoming event signatures is NP-complete. Hardness holds when every letter has one support of size three.Theorem · computational complexity classificationSelf-contained reduction from three-dimensional matching; exact finite reduction audit passesEvidence and limits →Automata and formal languagesPrefix quotients under shuffleNP-completeness proofFPRD-SH-T15; Karp's NP-completeness of three-dimensional matchingFPRD reduction from the classical three-dimensional matching problemReviewed 2026-09-01No documented external or specialist review of these FPRD results is recorded.Identify tractable policy classes and parameterizations for the compatibility clique number.
FPRD-SH-T17For a fixed flat memoryless Boolean-product expression, let TσT_\sigma be the useful canonical product states entered by event signature σ\sigma. Then Δ(E)=∑σ∣Tσ∣−∣⋃σTσ∣\Delta(E)=\sum_\sigma|T_\sigma|-|\bigcup_\sigma T_\sigma|. Inclusion–exclusion needs only compatibility cliques; with one support per letter these are exactly support matchings. The pair-intersection bound is exact iff no state receives three or more signatures.Theorem · exact global state-count identitySelf-contained double-counting and inclusion–exclusion proof; complete finite audit passesEvidence and limits →Automata and formal languagesPrefix quotients under shuffleGlobal collision calculusFPRD-SH-T12; FPRD-SH-T15; Finite inclusion–exclusionFPRD global consequence of the Boolean-product event-signature expansionReviewed 2026-09-01No documented external or specialist review of these FPRD results is recorded.Optimize the matching-indexed target intersections for overlapping one-support policies.
FPRD-SH-T18For a one-support-per-letter policy with pairwise-disjoint active supports, let NaN_a be the number of useful states in the synchronous block advanced by letter aa, let rr be the number of active letters, and let M=∏aNaM=\prod_aN_a. Then Δ(E)=∑a(Na−1)∏b≠aNb−(M−1)=(r−1)M−M∑aNa−1+1\Delta(E)=\sum_a(N_a-1)\prod_{b\ne a}N_b-(M-1)=(r-1)M-M\sum_aN_a^{-1}+1. Pure shuffle is the singleton-support specialization.Theorem · exact prescribed-size global overheadSelf-contained Cartesian-factorization proof; strict-gap scope corrected and independently auditedEvidence and limits →Automata and formal languagesPrefix quotients under shuffleDisjoint-support overhead theoremFPRD-SH-T17; Pairwise-disjoint event supports; Useful synchronous block productsFPRD extension of the shuffle and Boolean-product automata frameworksReviewed 2026-09-01No documented external or specialist review of these FPRD results is recorded.Determine the exact prescribed-size maximum when one-support events overlap.
FPRD-SH-T19Create one primary selector item for every policy signature σ=(a,S)\sigma=(a,S), with an off option and an on option containing each participant in SS as a nonprimary item colored aa. XCC solutions are then in bijection with cliques of the signature-compatibility graph. With one support per letter, they are exactly support-hypergraph matchings.Theorem · exact sparse constraint compilationSelf-contained bijection proof; exhaustive color-consistency audit passesEvidence and limits →Automata and formal languagesPrefix quotients under shuffleExact-cover-with-colors compilationFPRD-SH-T15; Knuth's exact covering with colorsFPRD compilation into Knuth's XCC modelReviewed 2026-09-01No documented external or specialist review of these FPRD results is recorded.Use FPRD-SH-T20 and FPRD-SH-T21 for the exact one-shot algorithm and its counting boundary.
FPRD-SH-T20For a graph GG, assign one letter aea_e and support ee to each edge, and give vertex vv the component expression ε+∑e∋vae\varepsilon+\sum_{e\ni v}a_e. Useful canonical product states are exactly graph matchings MM, the state for MM has ∣M∣|M| incoming signatures, and Δ(G)=∑M(∣M∣−1)+\Delta(G)=\sum_M(|M|-1)_+.Theorem · exact automata-to-matching correspondenceSelf-contained all-graph proof; exact product exploration audit passesEvidence and limits →Automata and formal languagesPrefix quotients under shuffleOne-shot matching modelFPRD-SH-T12; FPRD-SH-T19; Finite graph matchingsFPRD one-shot specialization of the Boolean-product frameworkReviewed 2026-09-01No documented external or specialist review of these FPRD results is recorded.Use the XCC compilation to enumerate matching receipts without constructing the canonical product.
FPRD-SH-T21Computing the one-shot overhead Δ(G)=∑M(∣M∣−1)+\Delta(G)=\sum_M(|M|-1)_+ is #P-complete under polynomial-time Turing reductions. If Z(G)Z(G) counts all graph matchings, then Z(G)=1+Δ(G⊔K2)−2Δ(G)Z(G)=1+\Delta(G\sqcup K_2)-2\Delta(G). Hardness therefore holds with size-two supports and depth-one component expressions.Theorem · exact counting-complexity classificationSelf-contained membership and isolated-edge reduction; exact finite audit passesEvidence and limits →Automata and formal languagesPrefix quotients under shuffleCounting-hardness boundaryFPRD-SH-T20; Valiant's #P-completeness of counting matchingsFPRD reduction from Valiant's classical matching-count problemReviewed 2026-09-01No documented external or specialist review of these FPRD results is recorded.Study sparse, bounded-width, and structurally restricted policy classes where XCC enumeration is effective.
FPRD-SH-T22For a one-support-per-letter policy with support family F⊆([n]r)\mathcal F\subseteq\binom{[n]}r, universal zero overhead is equivalent to F\mathcal F being independent in KGn,rKG_{n,r}. If n<2rn<2r, every support family has zero overhead. If n≥2rn\geq2r, then ∣F∣≤(n−1r−1)|\mathcal F|\leq\binom{n-1}{r-1}; for n>2rn>2r, equality requires a full star. When r≥2r\geq2, n>2rn>2r, and the core is empty, the sharp Hilton–Milner ceiling is (n−1r−1)−(n−r−1r−1)+1\binom{n-1}{r-1}-\binom{n-r-1}{r-1}+1. At n=2rn=2r, maximum families choose one support from each complementary pair, and empty-core examples exist for r≥2r\geq2.Theorem · classical extremal transfer and sharp boundaryExact automata reduction with classical EKR and Hilton–Milner inputs; equality cases auditedEvidence and limits →Automata and formal languagesPrefix quotients under shuffleUniform-support trichotomyFPRD-SH-T14; Erdős–Ko–Rado theorem; Hilton–Milner theoremFPRD automata transfer of the Erdős–Ko–Rado and Hilton–Milner theoremsReviewed 2026-09-01No documented external or specialist review of these FPRD results is recorded.Use FPRD-SH-T23 for the quantitative receipt once the EKR ceiling is crossed.
FPRD-SH-T23Assume 1≤r≤n/21\leq r\leq n/2. Let N=(nr)N=\binom nr, d=(n−rr)d=\binom{n-r}r, τ=(n−r−1r−1)\tau=\binom{n-r-1}{r-1}, and α=(n−1r−1)\alpha=\binom{n-1}{r-1}. If an rr-uniform policy has m>αm>\alpha supports, then its number of disjoint pairs is at least ⌈d+τ2Nm(m−α)⌉\left\lceil\frac{d+\tau}{2N}m(m-\alpha)\right\rceil. The depth-one one-shot overhead dominates this count.Theorem · spectral collision and overhead lower boundSelf-contained spectral derivation from the known Kneser spectrum; exact finite audit passesEvidence and limits →Automata and formal languagesPrefix quotients under shuffleSpectral collision receiptFPRD-SH-T20; Kneser graph spectrum; Rayleigh quotientFPRD composition of the classical Kneser spectrum with the one-shot matching theoremReviewed 2026-09-01No documented external or specialist review of these FPRD results is recorded.Replace the general spectral receipt with the exact diversity and supersaturation hierarchy in its valid parameter ranges.
FPRD-SH-T24For an rr-uniform support family F\mathcal F, let m=∣F∣m=|\mathcal F|, let dd be its maximum participant degree, let γ=m−d\gamma=m-d, and let q(F)q(\mathcal F) count disjoint support pairs. Then q(F)≥γmax⁡{0,d−[(n−1r−1)−(n−r−1r−1)]}q(\mathcal F)\geq\gamma\max\{0,d-[{n-1\choose r-1}-{n-r-1\choose r-1}]\}. Every counted pair is a realizable two-signature prefix-splitting receipt.Theorem · quantitative obstruction certificateSelf-contained all-length counting proof; complete small-family audit passesEvidence and limits →Automata and formal languagesPrefix quotients under shuffleDiversity obstruction receiptFPRD-SH-T14; FPRD-SH-T15; Uniform support countingFPRD translation of an elementary extremal-set countReviewed 2026-09-01No documented external or specialist review of these FPRD results is recorded.Test sharpness at the first positive-overhead layer and determine how pair receipts aggregate into total prefix-state overhead.
FPRD-SH-T31Let xx be a maximum-degree participant, let A\mathcal A be the supports through xx, and let B\mathcal B be the γ\gamma exceptional supports avoiding xx. Every compatible signature family is either a matching N⊆BN\subseteq\mathcal B, or N∪{A}N\cup\{A\} for exactly one compatible A∈AA\in\mathcal A. The target-set collision identity therefore gives an exact algorithm using O(∣F∣2γ)O(|\mathcal F|2^\gamma) target-intersection oracle calls, without enumerating the component product.Theorem · exact fixed-parameter target factorizationSelf-contained proof; exact policy-valid target audit passesEvidence and limits →Automata and formal languagesPrefix quotients under shuffleDiversity factorization theoremFPRD-SH-T17; FPRD-SH-T19; Support-family diversityKupavskii (2018) supplies the diversity parameter; the target factorization is an FPRD deductionReviewed 2026-09-01No documented external or specialist review of these FPRD results is recorded.Test the factorization against an externally posed problem before extending the framework further.
FPRD-SH-T32Group each hub support AA by μ(A)={j:A∩Bj≠∅}⊆[γ]\mu(A)=\{j:A\cap B_j\ne\varnothing\}\subseteq[\gamma]. This is the coarsest quotient preserving compatibility with every exceptional matching. A subset-zeta transform computes exact one-shot overhead in O(∣F∣rγ+γ2γ)O(|\mathcal F|r\gamma+\gamma2^\gamma) time and O(2γ)O(2^\gamma) auxiliary space.Theorem · fixed-parameter algorithm and canonical quotientSelf-contained proof; complete small-domain and sharpness audits passEvidence and limits →Automata and formal languagesPrefix quotients under shuffleConflict-mask quotient and zeta algorithmFPRD-SH-T20; FPRD-SH-T31; Subset zeta transformFPRD automata specialization using the classical subset-zeta transform of Björklund et al.Reviewed 2026-09-01No documented external or specialist review of these FPRD results is recorded.Seek an independently motivated application; do not optimize the same kernel in isolation.
FPRD-SH-T33Let C⊆F\mathcal C\subseteq\mathcal F be any pairwise-intersecting support family and B=F∖C\mathcal B=\mathcal F\setminus\mathcal C, with ∣B∣=k|\mathcal B|=k. Every compatible family is an exceptional matching in B\mathcal B, with at most one compatible member of C\mathcal C. Hence the target-oracle and one-shot factorizations hold with kk in place of diversity. Among decompositions obtained from one intersecting core, the smallest possible exception count is κ(F)=τ(DF)\kappa(\mathcal F)=\tau(D_{\mathcal F}), and κ≤γ\kappa\le\gamma.Theorem · optimal intersecting-core decompositionSelf-contained proof; exact minimum-cover and target audits passEvidence and limits →Automata and formal languagesPrefix quotients under shuffleIntersecting-core factorizationFPRD-SH-T17; FPRD-SH-T31; Minimum vertex coverFPRD correction using an elementary disjointness-graph decomposition; Harris–Narayanaswamy (2024) is the algorithmic comparatorReviewed 2026-09-01No documented external or specialist review of these FPRD results is recorded.Use kappa only as the optimum of this supplied-core decomposition; do not infer a general arithmetic lower bound.
FPRD-SH-B10For every prime power qq, the line supports of PG(2,q)PG(2,q) are pairwise intersecting, so κ=0\kappa=0. There are q2+q+1q^2+q+1 supports and every participant lies on q+1q+1 of them, so closest-star diversity is γ=q2\gamma=q^2. Thus γ−κ\gamma-\kappa is unbounded within the intersecting-core decomposition.Boundary result · unbounded parameter gapSelf-contained finite-geometry proof; exact q=2,3,5 controls passEvidence and limits →Automata and formal languagesPrefix quotients under shuffleUnbounded diversity gapFPRD-SH-T33; Dembowski, Finite GeometriesDembowski (1968) supplies the projective-plane incidence facts; the kernel comparison is an FPRD boundary controlReviewed 2026-09-01No documented external or specialist review of these FPRD results is recorded.Do not describe diversity as a complete or optimal search kernel.
FPRD-SH-C18Exact checks cover 1,088 complete support families, 31,377 matching states across complete and larger controls, 1,200 policy-valid target systems with 7,281 useful states, and projective planes of orders 2, 3, and 5. Direct enumeration and the minimum-cover kernel agree in every case.Computational finding · corrected-kernel auditAll exact checks pass; deterministic rerun is byte-identicalEvidence and limits →Automata and formal languagesPrefix quotients under shuffleIntersecting-core auditFPRD-SH-T33; FPRD-SH-B10; Exact enumerationFPRD Lab intersecting-core verifierReviewed 2026-09-01No documented external or specialist review of these FPRD results is recorded.Retain as supporting evidence; arbitrary-size conclusions come from the proofs.
FPRD-SH-B11With the slice length encoded in unary, exact counting of the Mazurkiewicz traces meeting a length slice of a DFA language is #P\#\mathrm P-complete even for the fixed independence graph with the single edge aIba\mathrel{\mathbb I}b. Thus the graph has vertex-cover number one, width two, maximum degree one, and matching number one. The hardness persists although every accepted reduction word has exactly one occurrence of the chosen cover letter. At cover number zero, traces are words and DFA length-slice counting is polynomial.Boundary theorem · published-hardness parameter extractionPublished parsimonious reduction; parameter corollary checked directlyEvidence and limits →Automata and formal languagesPrefix quotients under shuffleTrace-cover hardness boundaryde Colnet–Meel–Mathur Theorem 3.2; Polynomial DFA word countingde Colnet, Meel, and Mathur (POPL 2026), Theorem 3.2; FPRD parameter extractionReviewed 2026-09-01The underlying parsimonious reduction was peer reviewed at POPL 2026; the vertex-cover extraction has no separate external review.Do not seek an FPT algorithm from an alphabet-only cover; also control the sequential presentation orbit exposed to the DFA.
FPRD-SH-T34Given an mm-state DFA and a supplied vertex cover BB of the independence graph with ∣B∣=κ|B|=\kappa, the nonempty one-Foata-step traces touching the DFA language, including their size distribution, can be counted exactly in O(∣Σ∣κ2κm)O(|\Sigma|\kappa 2^\kappa m) time and O(2κm)O(2^\kappa m) auxiliary space.Theorem · exact fixed-parameter algorithmSelf-contained proof; exhaustive and randomized exact audits passEvidence and limits →Automata and formal languagesPrefix quotients under shuffleOne-step cover dynamic programFPRD-SH-T33; DFA subset dynamic programming; Foata stepsFPRD trace specialization of the intersecting-core decompositionReviewed 2026-09-01No documented external or specialist review of these FPRD results is recorded.Use this as the exact scope boundary; any lift to full traces must add a parameter controlling sequential residual amplification.
FPRD-SH-C19Direct trace-step enumeration and the cover dynamic program agree on all 64 four-letter independence graphs, all 65,536 complete two-state DFA instances and final sets, 2,500 larger deterministic controls, and 4,000 DNF reduction-pattern controls. Two complete runs are byte-identical.Computational finding · algorithm and boundary auditAll exact checks pass; deterministic rerun is byte-identicalEvidence and limits →Automata and formal languagesPrefix quotients under shuffleTrace-cover exact auditFPRD-SH-B11; FPRD-SH-T34; Exact enumerationFPRD Lab trace-cover verifierReviewed 2026-09-01No documented external or specialist review of these FPRD results is recorded.Retain as supporting evidence; the arbitrary-size conclusions come from the proof and the published reduction.
FPRD-SH-B09The canonical hub quotient can have all 2γ2^\gamma conflict classes, and only γ+1\gamma+1 pairwise-disjoint supports already give 2γ+12^{\gamma+1} XCC solutions. Explicit quotient materialization and solution enumeration can require exponential size. Neither construction proves that arithmetic evaluation requires 2Ω(γ)2^{\Omega(\gamma)} time.Boundary result · sharp representation and output costsExplicit constructions and exact formulas provedEvidence and limits →Automata and formal languagesPrefix quotients under shuffleSharpness and scope boundaryFPRD-SH-T31; FPRD-SH-T32; FPRD-SH-T21FPRD explicit construction and scope analysisReviewed 2026-09-01No documented external or specialist review of these FPRD results is recorded.Do not claim an arithmetic lower bound without a separate parameterized reduction.
FPRD-SH-C17Exact checks cover 33,856 complete support families, 738,063 matching states, 2,000 policy-valid target systems with 24,636 useful states, both small-diversity boundaries, and both sharpness constructions. All checks pass; a complete rerun is byte-identical.Computational finding · exact algorithm and boundary auditAll exact checks passEvidence and limits →Automata and formal languagesPrefix quotients under shuffleDiversity-kernel auditFPRD-SH-T31; FPRD-SH-T32; FPRD-SH-B09; Exact enumerationFPRD Lab diversity-kernel verifier and independent result reviewReviewed 2026-09-01No documented external or specialist review of these FPRD results is recorded.Retain as evidence; arbitrary-size conclusions come from the proofs.
FPRD-SH-C11Exact enumeration checks 1,082,432 support families in four complete small domains, all 182 maximal intersecting families at (n,r)=(7,3)(n,r)=(7,3), and 640 deterministic larger policies. The EKR, Hilton–Milner, complementary-pair, spectral, and one-shot matching receipts all agree; the 175 maximum empty-core (7,3)(7,3) families are exactly the classical equality constructions.Computational finding · extremal and spectral auditSource replay and independent boundary audit pass; T22/T23 hypotheses correctedEvidence and limits →Automata and formal languagesPrefix quotients under shuffleUniform-support exact auditFPRD-SH-T22; FPRD-SH-T23; FPRD-SH-T24; Exact enumerationFPRD Lab uniform-support verifierReviewed 2026-09-01No documented external or specialist review of these FPRD results is recorded.Retain as implementation evidence; use the classical theorems and spectral proof for arbitrary parameters.
FPRD-SH-T25Let JψJ_\psi join distinct signatures whose nonempty supports overlap. Define ψ⊗k\psi^{\otimes k} on the participant universe UkU^k by S(a1,…,ak)=Sa1×⋯×SakS_{(a_1,\ldots,a_k)}=S_{a_1}\times\cdots\times S_{a_k}. Then Jψ⊗k=Jψ⊠kJ_{\psi^{\otimes k}}=J_\psi^{\boxtimes k}.Theorem · exact policy-to-graph-product correspondenceSelf-contained all-length proof; exhaustive finite tensor audit passesEvidence and limits →Automata and formal languagesPrefix quotients under shuffleSupport-tensor theoremFPRD-SH-T15; Strong graph product; Cartesian products of finite supportsFPRD deduction in the strong-product framework of Lovász (1979)Reviewed 2026-09-01No documented external or specialist review of these FPRD results is recorded.Use FPRD-SH-T26 as a policy-level capacity dictionary; keep expression reachability as a separate proof obligation.
FPRD-SH-T26With Ω(ψ)=α(Jψ)\Omega(\psi)=\alpha(J_\psi) and Ω∞(ψ)=sup⁡k≥1Ω(ψ⊗k)1/k\Omega_\infty(\psi)=\sup_{k\ge1}\Omega(\psi^{\otimes k})^{1/k}, the support-tensor theorem gives Ω∞(ψ)=Θ(Jψ)\Omega_\infty(\psi)=\Theta(J_\psi). Every finite simple graph occurs as JψJ_\psi for a uniform support policy.Theorem · exact asymptotic-capacity identitySelf-contained corollary and constructive graph-representation proof; exact audit passesEvidence and limits →Automata and formal languagesPrefix quotients under shuffleShannon-capacity identityFPRD-SH-T25; FPRD-SH-T15; Definition of Shannon capacityFPRD automata interpretation of classical Shannon capacityReviewed 2026-09-01No documented external or specialist review of these FPRD results is recorded.Compile structured graph codes into reachable expression automata without treating tensor vertices as already-reachable letters.
FPRD-SH-B03For the complete rr-uniform policy, Jψ=KGn,r‾J_\psi=\overline{KG_{n,r}}. If r∣nr\mid n, its capacity is n/rn/r; if r∤nr\nmid n, the one-shot packing ⌊n/r⌋\lfloor n/r\rfloor and fractional/Lovász ceiling n/rn/r diverge. The first complete two-support case is T5=KG5,2‾T_5=\overline{KG_{5,2}}, with published values α(T5⊠d)=2,5,12,27\alpha(T_5^{\boxtimes d})=2,5,12,27 for d=1,2,3,4d=1,2,3,4.Boundary result · reduction to a published graph-capacity problemExact reduction to the published triangular-graph capacity problem; no new capacity bound claimedEvidence and limits →Automata and formal languagesPrefix quotients under shuffleComplement-of-Kneser boundaryFPRD-SH-T26; Kneser graphs; Triangular-graph capacity resultsKizhakkepallathu, Östergård, and Popa (2013)Reviewed 2026-09-01The triangular-graph bounds are published; the FPRD policy translation has no external review.Determine or tighten 60 <= alpha(T5 strong-power 5) <= 67 with symmetry-reduced XCC/DLX.
FPRD-SH-C12Exact enumeration checks 39,693 tensor vertex pairs, uniform policy representations of all 1,099 graphs through five vertices, tensor identities for every graph through four vertices, the complete two-support realization of T5T_5, and cyclic pair policies through C9C_9. All graph, tensor, and cyclic identities pass.Computational finding · Shannon bridge auditAll exact checks passEvidence and limits →Automata and formal languagesPrefix quotients under shuffleSupport-tensor exact auditFPRD-SH-T25; FPRD-SH-T26; FPRD-SH-B03; Exact enumerationFPRD Lab support-tensor verifierReviewed 2026-09-01No documented external or specialist review of these FPRD results is recorded.Use the verified policy dictionary as a gate before claiming any expression-level realization.
FPRD-SH-T27If the support-overlap graph JψJ_\psi is perfect, then Ω∞(ψ)=Ω(ψ)=α(Jψ)\Omega_\infty(\psi)=\Omega(\psi)=\alpha(J_\psi). Thus the Cartesian support-tensor packing rate is already attained in one layer. Pure shuffle and full synchronization are the empty- and complete-graph boundary cases.Corollary · exact no-amplification criterionSelf-contained sandwich proof from classical perfect-graph and Lovász-theta factsEvidence and limits →Automata and formal languagesPrefix quotients under shufflePerfect-policy criterionFPRD-SH-T26; Perfect graph theorem; Lovász theta sandwichFPRD corollary from Lovász's perfect-graph theorem (1972) and theta sandwich (1979)Reviewed 2026-09-01No documented external or specialist review of these FPRD results is recorded.Use perfect-graph recognition as a policy compiler gate before finite-power XCC search.
FPRD-SH-X03Give letter aia_i the adjacent-pair support {i,i+1}\{i,i+1\} on a five-participant cycle. Then Jψ=C5J_\psi=C_5, Ω(ψ)=2\Omega(\psi)=2, and the tensor-square signatures {(i,2i mod 5):i∈Z5}\{(i,2i\bmod5):i\in\mathbb Z_5\} are pairwise compatible, so Ω(ψ⊗2)=5>4=Ω(ψ)2\Omega(\psi^{\otimes2})=5>4=\Omega(\psi)^2 and Ω∞(ψ)=5\Omega_\infty(\psi)=\sqrt5.Exact example · strict support-tensor amplificationExplicit five-signature certificate; exact Lovász upper boundEvidence and limits →Automata and formal languagesPrefix quotients under shufflePentagon policy splitFPRD-SH-T25; FPRD-SH-T26; Lovász's pentagon capacity theoremFPRD cyclic-policy translation of Lovász's classical C5 codeReviewed 2026-09-01No documented external or specialist review of these FPRD results is recorded.Use FPRD-SH-X04 for the expression-level realization; next compile the typed recursive C7 gadget rather than enumerating its output.
FPRD-SH-B04For adjacent-pair supports on seven participants, Jψ=C7J_\psi=C_7, so Ω∞(ψ)=Θ(C7)\Omega_\infty(\psi)=\Theta(C_7). The current Lean-verified recursive certificate in C7⊠200C_7^{\boxtimes200} gives Ω∞(ψ)≥3.258805369885…\Omega_\infty(\psi)\ge3.258805369885\ldots, while the Lovász upper bound is below 3.31773.3177.Boundary result · externally anchored support-policy rateExact policy reduction; current graph-capacity bounds imported from primary sourcesEvidence and limits →Automata and formal languagesPrefix quotients under shuffleSeven-cycle policy boundaryFPRD-SH-T26; C7 Shannon-capacity boundsBuys, Polak, and Zuiddam (2026), using Gao's product methodReviewed 2026-09-01The lower bound is a current preprint; the FPRD automata translation has no external review.Use FPRD-SH-X06/T30 as the compiled five-dimensional base; next test whether residual quotients compose across Gao's typed product DAG without expanding its output.
FPRD-SH-T28Let G=JψG=J_\psi be the conflict graph of a one-support-per-letter policy, use optional-once component expressions, and let π:G→G‾\pi:G\to\overline G be a complementing permutation. The synchronized product with a π\pi-relabelled copy has exactly 1+∣V(G)∣1+|V(G)| reachable natural-prefix states, and its last-signature section {(v,π(v)):v∈V(G)}\{(v,\pi(v)):v\in V(G)\} is independent in G⊠2G^{\boxtimes2}.Theorem · reachable expression compilerSelf-contained all-length proof; exhaustive complementing-permutation audit passesEvidence and limits →Automata and formal languagesPrefix quotients under shuffleTwisted-section compilerFPRD-SH-T12; FPRD-SH-T14; Self-complementary graphsFPRD expression-level compiler for the classical self-complementary square codeReviewed 2026-09-01No documented external or specialist review of these FPRD results is recorded.Use self-complementary Paley graphs as further square calibrations; use the separate path compiler FPRD-SH-X06 for C7.
FPRD-SH-X04For the optional-once five-cycle expression, the useful component-prefix product has 11 states and the natural prefix automaton has 16. Synchronizing it with the copy relabelled by i↦2i(mod5)i\mapsto2i\pmod5 has only six reachable natural-prefix states; its five noninitial last-signature pairs are exactly {(i,2i):i∈Z5}\{(i,2i):i\in\mathbb Z_5\}, a nonrectangular independent set of size five in C5⊠2C_5^{\boxtimes2}.Exact example · reachable expression-level twisted sectionExplicit expression, exact state/transition counts, and executable auditEvidence and limits →Automata and formal languagesPrefix quotients under shuffleReachable pentagon twistFPRD-SH-T28; FPRD-SH-X03; FPRD-SH-T12FPRD reachable realization of Lovász's classical pentagon codeReviewed 2026-09-01No documented external or specialist review of these FPRD results is recorded.Use this as calibration while defining a nonvacuous succinct-generator resource.
FPRD-SH-T29For D⊆A2D\subseteq A^2, let Dx={y:(x,y)∈D}D_x=\{y:(x,y)\in D\} and index intermediate states by the distinct nonempty sets R∈{Dx}R\in\{D_x\}. The transitions r→xpDxr\xrightarrow{x}p_{D_x} and pR→yrp_R\xrightarrow{y}r recognize D∗D^*. This residual quotient is reversible iff its distinct successor sets are pairwise disjoint, and it is a graph-language for GG iff DD is independent in G⊠2G^{\boxtimes2}.Compiler lemma · exact residual quotient, reversibility, and validity criteriaSelf-contained proof; exhaustive small-relation audit and corrected standard-alphabet C7 regression passEvidence and limits →Automata and formal languagesPrefix quotients under shuffleReversible two-block compilerFPRD-SH-X04; Partial reversible DFAs; Strong-product independenceFPRD compiler lemma calibrated against Meiburg's reversible-capacity constructionReviewed 2026-09-01No documented external or specialist review of these FPRD results is recorded.Generalize the distinct-successor-set quotient to the typed five-block compiler and test compositional residual minimization across Gao's product nodes.
FPRD-SH-B05If a classical graph-language L⊆V(G)∗L\subseteq V(G)^* has growth ρ\rho, then every slice L∩V(G)nL\cap V(G)^n is independent in G⊠nG^{\boxtimes n}, and for every ε>0\varepsilon>0 some finite slice has root rate above ρ−ε\rho-\varepsilon. Reversible state splitting can compress or organize code families, but cannot yield a classical lower bound that does not factor through ordinary finite independent sets.Calibration boundary · exact slice factorizationDefinition-level proof; consistent with the primary regular-language capacity frameworkEvidence and limits →Automata and formal languagesPrefix quotients under shuffleNo-free-capacity boundaryDefinition of graph-language growth; Definition of Shannon capacityDirect consequence of Meiburg's graph-language formulationReviewed 2026-09-01Meiburg's regular-language framework is peer-reviewed; the FPRD methodological boundary has no documented specialist review.Measure succinctness and verification cost separately from code size; call a capacity result new only when an emitted finite slice improves a published bound.
FPRD-SH-C13The exact audit verifies the one-layer 11/16-state construction, the six-state reachable synchronized square, its five nonrectangular pentagon signatures, the six-state reversible lowering, both compiler criteria over all 530 two-block relations through three symbols, the corrected standard-alphabet six-state C7 residual quotient, 4,130 graph-language checks, and 265 complementing-permutation certificates through five vertices. All checks pass.Computational finding · expression and reversible compiler auditAll exact checks passEvidence and limits →Automata and formal languagesPrefix quotients under shuffleExpression-twist exact auditFPRD-SH-T28; FPRD-SH-X04; FPRD-SH-T29; Exact enumerationFPRD Lab expression-twist verifier, corrected by the independent result reviewReviewed 2026-09-01No documented external or specialist review of these FPRD results is recorded.Retain as implementation evidence; use the symbolic proofs for arbitrary graphs and code relations.
FPRD-SH-B06The reachable six-state construction of FPRD-SH-X04 presents each pair (i,2i)(i,2i) as one synchronized macro-event. The direct word expression R5=(a0a0+a1a2+a2a4+a3a1+a4a3)∗R_5=(a_0a_0+a_1a_2+a_2a_4+a_3a_1+a_4a_3)^* presents the same code as two original-alphabet events along a path. Its length-2m2m slice is the classical independent language CmC^m, where C={00,12,24,31,43}C=\{00,12,24,31,43\}. Reachability of the former does not determine the natural-prefix state count of the latter.Boundary · exact separation of macro-event and path-language realizationsSelf-contained comparison; the graph language is explicit in the primary automata-capacity literatureEvidence and limits →Automata and formal languagesPrefix quotients under shuffleMacro-event versus path compilerFPRD-SH-X04; FPRD-SH-T29; Graph languagesMeiburg (2025); FPRD comparison with the prefix construction of Broda et al. (2021)Reviewed 2026-09-01The graph-language construction is peer reviewed; the FPRD prefix comparison has no external review.Fix a resource measure that does not count a hard-coded block expression as an automata-specific capacity improvement.
FPRD-SH-X05For R5=(a0a0+a1a2+a2a4+a3a1+a4a3)∗R_5=(a_0a_0+a_1a_2+a_2a_4+a_3a_1+a_4a_3)^*, the Broda--Maia--Moreira--Reis backward prefix construction has the eleven states ε\varepsilon, R5aiR_5a_i, and R5aia2iR_5a_i a_{2i}. Merging ε\varepsilon with the five completed-block states gives a minimal six-state partial reversible DFA for the same language.Exact example · natural-prefix-to-reversible-quotient calibrationExact symbolic derivation and independent automaton auditEvidence and limits →Automata and formal languagesPrefix quotients under shuffleEleven-to-six direct block compilerFPRD-SH-B06; The prefix-automaton backward recursionFPRD calculation from Broda et al.'s prefix constructionReviewed 2026-09-01No documented external or specialist review of these FPRD results is recorded.Compare natural-prefix and compact-generator size only after fixing a uniform resource model.
FPRD-SH-C14An independent verifier checks all 488,281 alphabet words of lengths zero through eight, all ten pentagon-code pairs, the eleven-state natural prefix automaton, and its minimal six-state reversible quotient. Exactly 781 tested words are accepted. All checks pass.Computational finding · direct-expression auditAll exact checks passEvidence and limits →Automata and formal languagesPrefix quotients under shuffleIndependent direct-expression audit certificateFPRD-SH-B06; FPRD-SH-X05; Exact enumerationFPRD Lab independent direct-block verifierReviewed 2026-09-01No documented external or specialist review of these FPRD results is recorded.Retain as regression evidence for the semantic separation; use symbolic proofs for all lengths.
FPRD-SH-X06The published 367-word independent set in C7⊠5C_7^{\boxtimes5} can be reconstructed without storing its vectors. The cyclic 382-word precursor and conflict filter leave 327 words. The 71-vertex, 85-edge extension graph has exactly eight maximum independent sets of size 40: they share a 37-word core and differ by one endpoint choice on each of three disjoint conflict edges. Three selector bits recover the published extension.Exact computational theorem · table-free code compilerIndependent reconstruction and exact maximum-set enumeration passEvidence and limits →Automata and formal languagesPrefix quotients under shuffleTable-free 367-code compilerPolak--Schrijver cyclic construction; Strong-product independence; Exact maximum-clique searchPolak and Schrijver (2019); FPRD reconstruction and extension-graph decompositionReviewed 2026-09-01No documented external or specialist review of these FPRD results is recorded.Treat the generated typed package, rather than a 367-vector input file, as the leaf of Gao's recursive compiler.
FPRD-SH-T30For coordinate order (0,2,3,4,1)(0,2,3,4,1), the minimal partial DFA accepting the published 367-word code has residual-layer counts (1,7,49,61,9,1)(1,7,49,61,9,1), hence 128 states and 424 transitions. Across all eight maximum extensions of the fixed 327-word core and all 120 coordinate orders, the published extension is the unique code attaining 128 states; the other minima are 129 or larger.Theorem · exact residual quotient and finite optimalityMyhill--Nerode proof for each order; all 960 extension/order pairs checked exactlyEvidence and limits →Automata and formal languagesPrefix quotients under shuffleResidual-optimal published extensionFPRD-SH-X06; Myhill--Nerode right residuals; Finite coordinate-order exhaustionFPRD residual compiler for the Polak--Schrijver codeReviewed 2026-09-01No documented external or specialist review of these FPRD results is recorded.Determine whether Gao's typed product operation admits a residual quotient computed compositionally from child packages.
FPRD-SH-C15A standard-library exact verifier reconstructs the published 367-code without an input table, enumerates all eight maximum 40-word extensions, checks 960 residual compilers, verifies Gao's eight private pairs, complementary transversals, and (321,26,20)(321,26,20) auxiliary partition, and reproduces the six-node split recurrence through M40M_{40}. All checks pass.Computational finding · C7 base compiler and recursive-interface auditAll exact checks passEvidence and limits →Automata and formal languagesPrefix quotients under shuffleC7 base-compiler auditFPRD-SH-X06; FPRD-SH-T30; Gao's private-pair product lemma; Exact integer arithmeticFPRD C7 compiler audit; Gao (2026), arXiv:2607.27869v1Reviewed 2026-09-01No documented external or specialist review of these FPRD results is recorded.Use the 204-node typed syntax DAG as the next compiler input; do not enumerate its 200-dimensional output.
FPRD-SH-X08Retain the ten fixed-length languages I,B,R,Q,PH,PV,X,O,H,VI,B,R,Q,P^{\mathrm H},P^{\mathrm V},X,O,H,V of a Gao gadget. The product code is the disjoint union of seven concatenation rectangles, and all ten output types close under a constant union/concatenation template. Twelve base syntax nodes and 32 nodes for each of six product steps give an exact 204-node typed syntax DAG denoting Gao's full M40M_{40}-word code without enumerating a product word.Exact example · resource-preserving typed-language translationStructural induction proved; exact cardinality audit reproduces Gao's M40Evidence and limits →Automata and formal languagesPrefix quotients under shuffleTyped product language compilerFPRD-SH-X06; FPRD-SH-C15; Gao's product lemma; Fixed-length regular-language concatenationFPRD translation of Gao (2026)Reviewed 2026-09-01No documented external or specialist review of these FPRD results is recorded.Retain this resource-preserving translation as the input for any later semantic minimization or comparison.
FPRD-SH-C16Exact Brzozowski-derivative closure of the 204-node typed expression DAG yields a deterministic partial path compiler with 192,771192{,}771 reachable canonical syntax states and 618,415618{,}415 transitions for Gao's M40M_{40}-word code in C7⊠200C_7^{\boxtimes200}. The computation closes all 201 depth layers without enumerating the code; the largest layer has 6,761 states.Computational finding · exact canonical syntax-compiler profileComplete canonical syntactic derivative closure; deterministic rerun and independent two-block semantic audit passEvidence and limits →Automata and formal languagesPrefix quotients under shuffleTwo-hundred-dimensional symbolic compiler auditFPRD-SH-X08; Brzozowski derivatives; Hash-consed regular-expression DAGsFPRD typed-language compiler and independent semantic auditReviewed 2026-09-01No documented external or specialist review of these FPRD results is recorded.Retain as exact implementation evidence; do not spend another run minimizing a presentation of the known Gao code.
FPRD-SH-B08The table-free base reconstruction, constant-template product DAG, and 192,771-state canonical symbolic lowering give a complete path-language presentation of Gao's known 200-dimensional code. They do not improve Θ(C7)\Theta(C_7), prove DFA minimality, or realize the code as a small last-signature image. Further minimization of this presentation is not presently a literature-recognized open problem.Boundary result · research-line closureExact scope boundary recordedEvidence and limits →Automata and formal languagesPrefix quotients under shuffleC7 compiler stopping boundaryFPRD-SH-X08; FPRD-SH-C16; Current C7 capacity boundsFPRD scope audit against Gao and Buys--Polak--ZuiddamReviewed 2026-09-01No documented external or specialist review of these FPRD results is recorded.Study exact XCC algorithms parameterized by support-family diversity.
FPRD-SH-C10Exact enumeration checks 16,384 signature subsets for XCC compatibility and 1,355 graphs for the one-shot product correspondence, weighted matching formula, and isolated-edge recovery identity. All 21,152 matching receipts and useful product states agree with the theorems.Computational finding · compiler and reduction auditSource replay and independent implementation passEvidence and limits →Automata and formal languagesPrefix quotients under shuffleDancing Links and matching auditFPRD-SH-T19; FPRD-SH-T20; FPRD-SH-T21; Exact enumerationFPRD Lab XCC and one-shot matching verifierReviewed 2026-09-01No documented external or specialist review of these FPRD results is recorded.Retain as implementation evidence; use the symbolic proofs for arbitrary policies and graphs.
FPRD-SH-C09Exact enumeration checks 65,536 target-set families, 2,924 one-support policies with 28,856 signature intersections, and 3,905 pure-shuffle state-count vectors comprising 809,710 noninitial product states. All collision identities, matching boundaries, closed formulas, and clique-bound gaps agree.Computational finding · theorem and boundary auditSource audit and independent complete-domain replay pass; strict-gap scope correctedEvidence and limits →Automata and formal languagesPrefix quotients under shuffleGlobal-overhead exact auditFPRD-SH-T17; FPRD-SH-T18; Exact finite enumerationFPRD Lab global-overhead verifierReviewed 2026-09-01No documented external or specialist review of these FPRD results is recorded.Retain as implementation evidence; use the symbolic proofs for arbitrary sizes.
FPRD-SH-C08Exact enumeration checks 16,452 two-letter support policies through arity three against every homogeneous unused, a∗a^*, and b∗b^* target assignment, and checks all 256 subinstances of the 2×2×22\times2\times2 three-dimensional-matching universe under the hardness reduction. Every comparison passes.Computational finding · theorem and reduction auditSource audit and independent complete-domain replay passEvidence and limits →Automata and formal languagesPrefix quotients under shuffleCompatibility and matching auditFPRD-SH-T15; FPRD-SH-T16; Exact clique and matching enumerationFPRD Lab signature-compatibility verifierReviewed 2026-09-01No documented external or specialist review of these FPRD results is recorded.Retain as an implementation audit; use the symbolic proofs for arbitrary arity.
FPRD-SH-C07The source enumeration checks 16,448 two-letter support policies at arities two and three, 11,736 rigid-policy/component combinations, 16,382 non-rigid starred witnesses, and 16,448 signature-expansion projections. An independent review covers all 16,452 policies at arities one through three and checks 172,128 same-letter support-pair occurrences at the unmarked boundary. Full synchronization and the pairwise-intersecting support triangle pass; pure shuffle fails uniqueness.Computational finding · theorem auditSource audit and independent complete small-policy review passEvidence and limits →Automata and formal languagesPrefix quotients under shufflePrefix-rigidity exact auditFPRD-SH-T12; FPRD-SH-T14; Exact homogeneous product constructorFPRD Lab Boolean-product prefix-rigidity verifierReviewed 2026-09-01No documented external or specialist review of these FPRD results is recorded.Retain as an implementation audit; use the symbolic proof for arbitrary arity.
FPRD-SH-C06Exact enumeration checks 8,192 combinations of two-state one-letter transition structures, all eight Boolean policies on the supports {1},{2},{1,2}\{1\},\{2\},\{1,2\}, and discrete or universal component partitions. All 5,408 predecessor-compatible cases satisfy product predecessor compatibility and exact quotient/product commutation. An independent boundary audit also checks 56,448 saturated initial-set pairs and 86,528 final-set pairs.Computational finding · theorem auditSource transition audit and independent initial/final boundary audit passEvidence and limits →Automata and formal languagesPrefix quotients under shuffleBoolean-product exact auditFPRD-SH-T11; Exact Boolean-product constructorFPRD Lab Boolean-product quotient verifierReviewed 2026-09-01No documented external or specialist review of these FPRD results is recorded.Retain this as an implementation audit; use the all-arity proof for the theorem.
FPRD-RE-D01For a regular expression BB, let QBQ_B be a finite Antimirov partial-derivative carrier containing BB and closed under one-letter partial derivatives.Definition · finite constructionClassical construction stated for the quotient proofEvidence and limits →Automata and formal languagesRegular expressions and quotientsFinite derivative carrierAntimirov partial derivativesAntimirov (1996) finiteness theorem; FPRD construction for Zhuchko's problemReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Make the carrier construction fully explicit in a mechanized implementation.
FPRD-RE-L01Interpreting 0,10,1, letters, union, concatenation, and star respectively as the empty relation, identity, partial-derivative edges, union, relational composition, and reflexive-transitive closure on QBQ_B gives (P,Q)∈⟦A⟧B(P,Q)\in\llbracket A\rrbracket_B exactly when some u∈L(A)u\in L(A) satisfies Q∈∂u(P)Q\in\partial_u(P).LemmaProved by structural inductionEvidence and limits →Automata and formal languagesRegular expressions and quotientsRelational semantics lemmaFPRD-RE-D01Problem proposed by Ekaterina Zhuchko; FPRD Lab constructionReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Obtain an independent check of the star case and its finite path bound.
FPRD-RE-T01For regular expressions A,BA,B, form the finite set of states Q∈QBQ\in Q_B reachable from BB through ⟦A⟧B\llbracket A\rrbracket_B, and let f(A,B)f(A,B) be their union as regular expressions. Then L(f(A,B))=L(A)−1L(B)={v:∃u∈L(A), uv∈L(B)}L(f(A,B))=L(A)^{-1}L(B)=\{v:\exists u\in L(A),\ uv\in L(B)\}.Theorem · constructive solutionProved under the finite-derivative interpretation of the requested constructionEvidence and limits →Automata and formal languagesRegular expressions and quotientsConstruction and correctness proofFPRD-RE-D01; FPRD-RE-L01Problem proposed by Ekaterina Zhuchko; FPRD Lab constructionReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Determine whether the finite carrier and relation saturation can be compiled away under the pinned model FPRD-RE-D02.
FPRD-RE-C01On 405 selected binary regular-expression pairs and all 31 suffixes of length at most four, three saved automata formulations agree in all 12,55512{,}555 membership comparisons. The Antimirov-versus-Thompson audit removes the first checker's normalization and derivative code, while a review audit replaces the epsilon-NFA oracle with an epsilon-free Glushkov position automaton. The first audit also detects four injected errors.Computational finding · reproducible finite auditReproduced by three saved checks; zero ordinary mismatches, identical semantic transcripts, four named negative controls detected, and 65 hostile star cases confirmedEvidence and limits →Automata and formal languagesRegular expressions and quotientsFinite audit and downloadable evidenceFPRD-RE-D01; FPRD-RE-L01; FPRD-RE-T01FPRD Lab replacement finite auditReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Use the exact unbounded star family as the next adversary rather than continuing to enlarge this bounded corpus.
FPRD-RE-D02A carrier-free constructor-only quotient compiler recurses on ordinary regular-expression constructors and returns an ordinary regular expression, without enumerating a residual carrier, saturating a finite relation, or adding an explicit least-fixed-point constructor.Definition attempt · strengthened construction disciplineInformal exclusion-based discipline; a formal compiler class is still missingEvidence and limits →Automata and formal languagesRegular expressions and quotientsConstructor-only formulation boundaryFPRD-RE-T01FPRD Lab formulation attempt for a stricter construction disciplineReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Specify an admissible compiler grammar, auxiliary-state policy, and equivalence/cost model before testing general existence or impossibility.
FPRD-RE-T02For languages K,LK,L, the quotient Q(K∗,L)Q(K^*,L) is the least fixed point of ΦK,L(X)=L∪Q(K,X)\Phi_{K,L}(X)=L\cup Q(K,X), hence Q(K∗,L)=⋃n≥0Q(Kn,L)Q(K^*,L)=\bigcup_{n\ge0}Q(K^n,L). On a finite derivative carrier of LL, this becomes finite reachability saturation.Theorem · presentation-dynamics decompositionProved directly from left-quotient compositionEvidence and limits →Automata and formal languagesRegular expressions and quotientsFixed-point theorem and proofFPRD-RE-L01; FPRD-RE-T01Elementary language-theoretic deduction; FPRD presentation-dynamics formulationReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Determine whether the finite star-orbit closure can be compiled uniformly into the stricter model FPRD-RE-D02.
FPRD-RE-X01For every k≥0k\ge0, ε∈(a∗)−1{ak+1}\varepsilon\in(a^*)^{-1}\{a^{k+1}\} but ε∉⋃i=0k{ai}−1{ak+1}\varepsilon\notin\bigcup_{i=0}^{k}\{a^i\}^{-1}\{a^{k+1}\}. Therefore no fixed finite quotient-depth truncation computes all star left quotients.Negative theorem · counterexample familyProved by an explicit unary familyEvidence and limits →Automata and formal languagesRegular expressions and quotientsUnbounded-unfolding proofFPRD-RE-T02FPRD Lab direct counterexample familyReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Use this family as the first adversary for any proposed carrier-free star compiler; seek a broader lower bound only after its formal interface is pinned.
FPRD-RE-B01Uniformly bounded star unfolding is impossible and finite derivative saturation is sufficient. A broader carrier-free existence question has not yet been posed as a formal mathematical problem because FPRD-RE-D02 does not define a quantified compiler class.Unresolved formalization boundaryNot yet a well-posed existence or impossibility problemEvidence and limits →Automata and formal languagesRegular expressions and quotientsInterpretation boundaryFPRD-RE-D02; FPRD-RE-T02; FPRD-RE-X01FPRD Lab strengthened formulation boundary, motivated by the Automata Exchange questionReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Specify an admissible compiler grammar, auxiliary-state policy, and equivalence/cost model before seeking a carrier-elimination theorem or lower bound.
FPRD-LT-D01Given a minimal DFA whose transition monoid M≤TQM\le T_Q is L\mathcal L-trivial and a target transformation f:Q→Qf:Q\to Q, the membership problem asks whether f∈Mf\in M.Definition · decision problemPrecisely stated; exact complexity remains open hereEvidence and limits →Automata and formal languagesL-trivial transformation membershipProblem statement and conventionsNo recorded dependenciesProblem proposed by Andrew Ryzhikov; FPRD Lab analysisReviewed 2026-08-25No documented external or specialist review of this FPRD result is recorded.Determine whether positive instances always admit polynomial-length word witnesses in the supplied transformation action.
FPRD-LT-L01For M=⟨τa:a∈Σ⟩M=\langle\tau_a:a\in\Sigma\rangle, membership of ff in MM is equivalent to membership of the same underlying element in MopM^{\mathrm{op}} after reversing a witnessing word; moreover L\mathcal L-triviality of MM is equivalent to R\mathcal R-triviality of MopM^{\mathrm{op}}.Lemma · algebraic dualityProved directly from opposite multiplicationEvidence and limits →Automata and formal languagesL-trivial transformation membershipOpposite multiplication and proofFPRD-LT-D01Problem proposed by Andrew Ryzhikov; FPRD Lab analysisReviewed 2026-08-25No documented external or specialist review of this FPRD result is recorded.Use the duality only together with an explicit size analysis of any representation of the opposite monoid.
FPRD-LT-T01If an nn-state L-trivial instance admits a polynomial-time computable faithful poDFA action ρ:Mop↪TP\rho:M^{\mathrm{op}}\hookrightarrow T_P of polynomial degree, explicit generator images, and a computable target code tft_f that equals ρ(f)\rho(f) for positive instances and lies outside ρ(M)\rho(M) for negative instances, then membership is in NP and positive instances have word certificates of length at most ∣P∣(∣P∣+1)/2|P|(|P|+1)/2.Theorem · conditional complexity transferProved conditionally; the compact dual representation is not known in generalEvidence and limits →Automata and formal languagesL-trivial transformation membershipConditional NP theoremFPRD-LT-L01; Ryzhikov–Wolf 2024, Proposition 9FPRD Lab conditional transfer using Ryzhikov–Wolf 2024, Proposition 9Reviewed 2026-08-25The poDFA representative bound is a published MFCS 2024 result; no external review of this conditional FPRD transfer is recorded.Construct a polynomial-degree faithful action of the opposite monoid or prove that no uniform construction exists.
FPRD-LT-T02Let M=⟨S⟩M=\langle S\rangle and let f:Q→Qf:Q\to Q be the target. A polynomial-time computable poDFA action ρ:Mop→TP\rho:M^{\mathrm{op}}\to T_P and code tf∈TPt_f\in T_P suffice for the conditional NP transfer when, for every g∈Mg\in M, ρ(g)=tf\rho(g)=t_f if and only if g=fg=f; full faithfulness of ρ\rho is unnecessary.Theorem · conditional quotient transferProved conditionally; a uniform compact target-isolating construction remains openEvidence and limits →Automata and formal languagesL-trivial transformation membershipTarget-fibre theorem and proofFPRD-LT-L01; Ryzhikov–Wolf 2024, Proposition 9FPRD Lab conditional theorem using Ryzhikov–Wolf 2024, Proposition 9Reviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Construct target-isolating poDFA observations directly from the supplied L-trivial action, beginning with fixed alphabets and principal-left-ideal features.
FPRD-LT-X01For the L-trivial monoid M={1,a,0}M=\{1,a,0\} with a2=0a^2=0, the target f=1f=1 has a two-state target-isolating poDFA quotient that maps aa and 00 to the same transformation; hence the quotient is nonfaithful while its target fibre is a singleton.Example · strict quotient compressionProved by a complete multiplication-table and action checkEvidence and limits →Automata and formal languagesL-trivial transformation membershipThree-element monoid exampleFPRD-LT-T02FPRD Lab exact exampleReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Search for canonical target-isolating congruences that retain poDFA order while collapsing large non-target regions.
FPRD-LT-C01The minimal two-state DFA for words ending in aa has L-trivial transition monoid {1,c0,c1}\{1,c_0,c_1\}, but reversing its transitions yields a nondeterministic automaton with a two-state cycle and a self-looping state having another outgoing transition on the same letter.Counterexample · failed reductionProved by an explicit two-state exampleEvidence and limits →Automata and formal languagesL-trivial transformation membershipTwo-state reversal counterexampleFPRD-LT-D01Problem proposed by Andrew Ryzhikov; FPRD Lab counterexampleReviewed 2026-08-25No documented external or specialist review of this FPRD result is recorded.Exclude graph reversal and matrix transposition from future dual-representation arguments unless functionality and order are proved.
FPRD-LT-E01Exhaustive enumeration of unordered pairs of distinct transformations on n=2,3,4n=2,3,4 states found maximum shortest-word diameters 1,2,31,2,3, respectively, among the binary L-trivial semiautomata that admit a minimal DFA final set.Computational findingFinite exhaustive evidence through four states; the inferred pattern is refuted at five statesEvidence and limits →Automata and formal languagesL-trivial transformation membershipEnumeration method and resultsFPRD-LT-D01FPRD Lab finite enumerationReviewed 2026-08-25No documented external or specialist review of this FPRD result is recorded.Retain these counts as the completed four-state baseline; use FPRD-LT-E02 for the five-state classification.
FPRD-LT-T03For every n ≥ 5, there is a minimal binary n-state DFA with J-trivial transition monoid and a target transformation whose shortest representative has length exactly n. Thus the conjectured n − 1 bound for binary L-trivial inputs is false already inside the J-trivial subclass.Theorem · exact witness familySelf-contained construction and proof; no external reviewEvidence and limits →Automata and formal languagesL-trivial transformation membershipBinary family and exact lower boundMasopust–Krötzsch 2021, confluent-poDFA characterization; Simon 1975, piecewise testability iff J-trivial syntactic monoidFPRD Lab construction using the Masopust–Krötzsch and Simon characterizationsReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Seek a polynomial upper bound for fixed binary alphabets or a family with superpolynomial shortest representatives; the linear lower bound alone does not settle complexity.
FPRD-LT-E02Among binary five-state semiautomata with L-trivial transition monoid that admit a minimal-DFA final set, exhaustive enumeration finds maximum shortest-word diameter 5. Up to state relabelling fixing the initial state and interchange of the two letters, there are 1,148 retained generator-pair classes and exactly three extremal classes.Computational finding · exhaustive classificationExact finite computation with an independent extremal auditEvidence and limits →Automata and formal languagesL-trivial transformation membershipFive-state exhaustive classificationFPRD-LT-D01FPRD Lab exact enumerationReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Use the explicit family in FPRD-LT-T03 as the corrected lower-bound baseline; do not infer a general upper bound from five states.
FPRD-LT-X02For the 14-element five-state extremal generated by a=(2,1,2,3,1) and b=(0,1,3,4,4), minimizing the left-Cayley poDFA with sole accepting element f=(4,1,1,1,1) gives a nine-state poDFA action whose transformation fibre over f is exactly {f}.Example · exact target-isolating quotientProved by exact partition refinement and fibre auditEvidence and limits →Automata and formal languagesL-trivial transformation membershipNine-state extremal quotientFPRD-LT-T02; FPRD-LT-E02FPRD Lab exact extremal analysisReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Find a quotient construction whose state space and fibre proof are obtained directly from the supplied n-state action rather than from the enumerated monoid.
FPRD-LT-T04For f∈M=η(Σ∗)f\in M=\eta(\Sigma^*), let Pf(x)={z∈M:zx=f}P_f(x)=\{z\in M:zx=f\} and df=∣{Pf(x):x∈M}∣d_f=|\{P_f(x):x\in M\}|. The minimal DFA of Kf={wR:η(w)=f}K_f=\{w^R:\eta(w)=f\} has exactly dfd_f states. If MM is L-trivial, this DFA is partially ordered, so every generated target has a representative of length at most df−1d_f-1.Theorem · canonical target observerSelf-contained Myhill–Nerode proof; no external reviewEvidence and limits →Automata and formal languagesL-trivial transformation membershipCanonical observer and path boundFPRD-LT-L01; Myhill–Nerode theorem; R-trivial language characterizationFPRD Lab target-specific synthesis using classical automata theoryReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Determine whether target-residual degree is polynomially bounded in the degree of every supplied L-trivial transformation action.
FPRD-LT-T05For the binary J-trivial family of FPRD-LT-T03, the source transition monoid has exactly ∣Mn∣=(n3)+n−1|M_n|=\binom n3+n-1 elements, while the canonical target-residual observer for fn=(n−1,1,…,1)f_n=(n-1,1,\ldots,1) has exactly dfn=(n2)−1d_{f_n}=\binom n2-1 states.Theorem · exact quotient familySelf-contained normal-form and residual proof with exact computational auditsEvidence and limits →Automata and formal languagesL-trivial transformation membershipExact monoid and observer formulasFPRD-LT-T03; FPRD-LT-T04FPRD Lab exact analysis of the binary lower-bound familyReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Generalize the fibre classification or construct an L-trivial family with superpolynomially many target profiles.
FPRD-LT-C02Among all 32,896 unordered transformation-generator pairs on four states, 4,473 generate L-trivial monoids. Their maximum left-Cayley height is 6, while the maximum shortest right-Cayley distance of any target across the same search is 3; ideal height is therefore a strict overestimate of target certificate length.Counterexample · complexity proxyExact finite computation; semigroup control rather than a minimal-DFA classificationEvidence and limits →Automata and formal languagesL-trivial transformation membershipFour-state Green-height controlFPRD-LT-D01FPRD Lab exhaustive four-state semigroup computationReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Use extension-distinguishable target profiles or actual target geodesics rather than principal-ideal height as the obstruction measure.
FPRD-LT-B01It remains open whether every positive L-trivial transformation-membership instance has a polynomial-length word witness in the degree of the supplied action. The canonical target-residual degree d_f gives a witness of length at most d_f−1; whether d_f is always polynomial is the current sufficient-bound question.Open problem · representation boundaryUnresolved; the n-minus-one conjecture is refuted, but neither NP membership nor PSPACE hardness is establishedEvidence and limits →Automata and formal languagesL-trivial transformation membershipWhat remains openFPRD-LT-T04; FPRD-LT-T05; FPRD-LT-C02; FPRD-LT-T03; FPRD-LT-E02Problem proposed by Andrew Ryzhikov; FPRD Lab boundary analysisReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Prove a polynomial upper bound on target-residual degree from L-trivial fibre evolution, or construct a structured superpolynomial target-profile or geodesic family.
FPRD-LRN-D01For F(q)=∑n≥0anqn∈Q[[q]]F(q)=\sum_{n\ge0}a_nq^n\in\mathbb Q[[q]], an exact-prefix learner receives a0,…,aN−1a_0,\ldots,a_{N-1}, while a revisable-snapshot learner receives polynomials PtP_t satisfying only ∀n ∃Tn ∀t≥Tn:[qn]Pt=an\forall n\,\exists T_n\,\forall t\ge T_n:[q^n]P_t=a_n.Definition · observation modelsPrecisely stated; the two models have different learnabilityEvidence and limits →Automata and formal languagesLearning rational sequencesObservation modelsNo recorded dependenciesProblem proposed by Benjamin Kaminski; FPRD Lab model analysisReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Determine which observation model is supplied by the probabilistic-program application motivating the revisable examples.
FPRD-LRN-T01A rational series of positive Hankel rank rr is determined and reconstructible from exactly 2r2r initial coefficients, and this count is sharp. With a known bound R≥rR\ge r, 2R2R coefficients give certified exact reconstruction; without a known rank bound, repeated reconstruction identifies every rational series in the limit. The rank-zero class contains only the zero series.Theorem · exact learningClassical recurrence reconstruction, restated and proved for this modelEvidence and limits →Automata and formal languagesLearning rational sequencesExact-prefix theoremFPRD-LRN-D01; Massey 1969 shift-register synthesis; Berstel–Reutenauer 2010 Hankel minimizationJames L. Massey (1969); Jean Berstel and Christophe Reutenauer (2010); FPRD sharpness proofReviewed 2026-09-01The recurrence-reconstruction theorem is classical; no external review of this FPRD exposition is recorded.Quantify coefficient bit growth for the intended application and add a certified-prefix extractor if its approximants provide one.
FPRD-LRN-C01After any prefix through degree N−1N-1, the distinct rational series F(q)F(q) and F(q)+cqN/(1−λq)F(q)+cq^N/(1-\lambda q), with c≠0c\ne0, agree on every observed coefficient. Therefore unrestricted exact-prefix learning cannot certify from finite data that its current rational hypothesis is final.Counterexample · finite identifiabilityProved by an explicit rational tailEvidence and limits →Automata and formal languagesLearning rational sequencesRational-tail indistinguishabilityFPRD-LRN-D01Problem proposed by Benjamin Kaminski; FPRD Lab boundary proofReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Identify a usable rank bound, equivalence query, or finality certificate in the intended application.
FPRD-LRN-T02No learner identifies every rational target in the limit from arbitrary polynomial snapshots PtP_t whose coefficients merely stabilize pointwise; the impossibility already holds using the zero series and single monomials qkq^k.Theorem · impossibilityProved by a diagonal presentationEvidence and limits →Automata and formal languagesLearning rational sequencesDiagonal impossibility theoremFPRD-LRN-D01Problem proposed by Benjamin Kaminski; FPRD Lab diagonal argumentReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Test the intended approximation semantics for a computable stabilization modulus, finality markers, monotone bounds, or active validation.
FPRD-LRN-B01A positive exact-learning theorem for revisable polynomial approximants requires more than pointwise stabilization, such as a computable stabilization modulus, finality markers, certified monotone bounds with an effective gap test, a detectable revision bound, or active coefficient and equivalence queries.Research boundaryNecessary direction isolated; application semantics remain unknownEvidence and limits →Automata and formal languagesLearning rational sequencesWhat would make learning possibleFPRD-LRN-T02Problem proposed by Benjamin Kaminski; FPRD Lab boundary analysisReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Recover the semantics of the probabilistic-program approximants and state the strongest available certificate before designing a learner.
FPRD-T96A causal resolver emits one call, return, or local tag in the same round as each observed input letter. Its one-stack product with a deterministic visible-stack machine has exactly the resolver state and tagged-machine configuration after every prefix. A fixed finite family of such products executes on parallel stacks and accepts exactly their finite disjunction. If the family is complete for every accepted tagged lift, its executor and the scaffold produced by the verified compiler decide exactly the forgotten-action projection, including at epsilon.Mechanically checked resultmechanically checkedEvidence and limits →Automata and formal languagesFormal languages and scaffolding automataformalizations/frontier-derivative/FrontierDerivative/ResolverCover.leanFPRD-T89FPRD governed claims ledgerReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Expose the formal/checker scope, reproducibility instructions, and the gap to a complete mathematical proof.
FPRD-T98A finalizable delayed resolver emits append-only online tagged batches and an explicit finish batch at end of word. Its semantic visible-stack evaluator has exactly the resolver state and direct visible run on the online output after every prefix, and after finish it has exactly the direct run on the completed annotation. A lawful fixed finite Complete Cover therefore recognizes exactly the forgotten-action projection, including at epsilon. This theorem does not invoke the strict compiler.Mechanically checked resultmechanically checkedEvidence and limits →Automata and formal languagesFormal languages and scaffolding automataformalizations/frontier-derivative/FrontierDerivative/DelayedResolver.leanFPRD-T96FPRD governed claims ledgerReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Expose the formal/checker scope, reproducibility instructions, and the gap to a complete mathematical proof.
FPRD-T18For every finite conventional context-free grammar G, nonterminal A, and input word w, the least relational suffix behavior of the canonical translation returns exactly the suffixes v for which A derives a terminal prefix x with w=xv; consequently complete-match observation of the translated start variable is exactly the classical language of G.Written-proof claiminformal proofEvidence and limits →Automata and formal languagesFormal languages and scaffolding automataOPEN_PROBLEMS.mdFPRD-D07; FPRD-D09; FPRD-T14; FPRD-T15FPRD governed claims ledgerReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Audit the proof against its dependencies and publish a self-contained evidence summary before increasing maturity.
FPRD-T19The canonical labeled translation of every finite conventional context-free grammar generates an M12 compact relational recognition dynamic reconstructed from its finite reachable graph shadows, and the complete-match call observation at its distinguished initial state is exactly the grammar's classical language.Written-proof claiminformal proofEvidence and limits →Automata and formal languagesFormal languages and scaffolding automataOPEN_PROBLEMS.mdFPRD-D08; FPRD-D09; FPRD-T16; FPRD-T17; FPRD-T18FPRD governed claims ledgerReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Audit the proof against its dependencies and publish a self-contained evidence summary before increasing maturity.
FPRD-T20Every finite positive relational presentation has a finite conventional CFG word normal form whose translated equation operator agrees in every environment, hence whose finite stages, exact and bounded least suffix solutions, and complete-match language agree exactly; together with the M13 lift, the complete-match languages of finite positive relational presentations are exactly the context-free languages.Written-proof claiminformal proofEvidence and limits →Automata and formal languagesFormal languages and scaffolding automataOPEN_PROBLEMS.mdFPRD-D07; FPRD-D09; FPRD-D10; FPRD-T14; FPRD-T15; FPRD-T18FPRD governed claims ledgerReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Audit the proof against its dependencies and publish a self-contained evidence summary before increasing maturity.
FPRD-T21For every labeled positive relational presentation, distributive CFG normalization induces a finite origin relation on call occurrences, and at every exact and bounded observation level each normalization-surviving source right-success frame behavior is the relational union of the frame behaviors of its normalized call clones; split, merge, and elimination witnesses show that raw presentation dynamics need not be invariant.Written-proof claiminformal proofEvidence and limits →Automata and formal languagesFormal languages and scaffolding automataOPEN_PROBLEMS.mdFPRD-D03; FPRD-D08; FPRD-D10; FPRD-T15; FPRD-T16; FPRD-T20FPRD governed claims ledgerReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Audit the proof against its dependencies and publish a self-contained evidence summary before increasing maturity.
FPRD-T22A language is regular exactly when its residual recognition dynamic is finite; in that case residual actions and empty-word output recognize it exactly, every reachable deterministic recognizer maps uniquely and surjectively onto the residual dynamic by accepted-future language, and the residual dynamic is the unique minimal exact recognizer up to labeled isomorphism, recovered after finite bounded observational refinement.Written-proof claiminformal proofEvidence and limits →Automata and formal languagesFormal languages and scaffolding automataOPEN_PROBLEMS.mdFPRD-D02; FPRD-D12FPRD governed claims ledgerReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Audit the proof against its dependencies and publish a self-contained evidence summary before increasing maturity.
FPRD-T23For languages A and B with positive minimum word length m in A, the operator F(X)=AX union B is at most 2-to-the-minus-m contractive in the shortest-distinguishing-word ultrametric, has the unique fixed point A-star B, and its finite unfoldings become exact on bounded words; under the suffix-recognition lift the same fixed point solves the corresponding relational composition-and-union equation with exact remaining-suffix and complete-match readout.Written-proof claiminformal proofEvidence and limits →Automata and formal languagesFormal languages and scaffolding automataOPEN_PROBLEMS.mdFPRD-D06; FPRD-D11; FPRD-T13FPRD governed claims ledgerReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Audit the proof against its dependencies and publish a self-contained evidence summary before increasing maturity.
FPRD-T24Every finite Greibach recognition presentation induces one-half contractive operators on the finite products of exact language behaviors and full set-valued suffix behaviors; both have unique fixed points, bottom unfoldings at depth N plus one are exact on words and input rows through length N, the vector suffix lift identifies the two solutions, and their readout equals ordinary finite CFG derivability.Written-proof claiminformal proofEvidence and limits →Automata and formal languagesFormal languages and scaffolding automataOPEN_PROBLEMS.mdFPRD-D02; FPRD-D06; FPRD-D11; FPRD-D13; FPRD-T13; FPRD-T14; FPRD-T15; FPRD-T18; FPRD-T23FPRD governed claims ledgerReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Audit the proof against its dependencies and publish a self-contained evidence summary before increasing maturity.
FPRD-T25A language is context-free exactly when it is the complete-match observation of the unique suffix fixed point of a finite Greibach recognition presentation; thus every context-free language has a finite terminal-delayed presentation with coherent exact bounded observations and uniform remaining-suffix readout.Written-proof claiminformal proofEvidence and limits →Automata and formal languagesFormal languages and scaffolding automataOPEN_PROBLEMS.mdFPRD-D09; FPRD-D13; FPRD-T18; FPRD-T24FPRD governed claims ledgerReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Audit the proof against its dependencies and publish a self-contained evidence summary before increasing maturity.
FPRD-T26For a finite cycle-guarded positive relational presentation with r variables, the occurrence-delay matrix bounds componentwise semantic first differences by min-plus multiplication, some power p at most r of the exact suffix operator is one-half contractive, the original operator has a unique fixed point, and bottom depth p times N plus one is exact on all input rows through length N with coherent inverse-limit recovery.Written-proof claiminformal proofEvidence and limits →Automata and formal languagesFormal languages and scaffolding automataOPEN_PROBLEMS.mdFPRD-D02; FPRD-D06; FPRD-D14; FPRD-T13FPRD governed claims ledgerReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Audit the proof against its dependencies and publish a self-contained evidence summary before increasing maturity.
FPRD-T27For every finite cycle-guarded positive relational presentation, the unique contractive-iterate fixed point is its M11 least fixed point and finite-derivation semantics, its bounded suffix and complete-match readouts are exact by the certified block depth, and its labeled M12 continuation actions are evaluated in that same uniquely determined behavior vector.Written-proof claiminformal proofEvidence and limits →Automata and formal languagesFormal languages and scaffolding automataOPEN_PROBLEMS.mdFPRD-D07; FPRD-D08; FPRD-D14; FPRD-T14; FPRD-T15; FPRD-T16; FPRD-T26FPRD governed claims ledgerReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Audit the proof against its dependencies and publish a self-contained evidence summary before increasing maturity.
FPRD-T28Every finite generalized Dyck-control presentation has a finite positive state-pair suffix equation system whose components recognize exactly the well-nested traces carrying the selected DFA between their endpoint states; every recursive dependency has positive delay, so the system has one exact suffix solution recovered at depth N plus one through trace length N, and letter-to-letter decoding gives exact remaining-suffix behavior on the output alphabet with the same bounded observation index.Written-proof claiminformal proofEvidence and limits →Automata and formal languagesFormal languages and scaffolding automataOPEN_PROBLEMS.mdFPRD-D15; FPRD-T18; FPRD-T22; FPRD-T26; FPRD-T27FPRD governed claims ledgerReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Audit the proof against its dependencies and publish a self-contained evidence summary before increasing maturity.
FPRD-T29For every nonempty finite output alphabet Sigma there are one finite generalized Dyck alphabet and one fixed letter-to-letter readout, depending only on Sigma, such that the exact suffix behaviors of context-free languages over Sigma are precisely the decoded observations obtained by varying a finite regular controller; every such observation is coherently reconstructed from the controller-product's finite shadows.Written-proof claiminformal proofEvidence and limits →Automata and formal languagesFormal languages and scaffolding automataOPEN_PROBLEMS.mdFPRD-D15; FPRD-T25; FPRD-T28FPRD governed claims ledgerReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Audit the proof against its dependencies and publish a self-contained evidence summary before increasing maturity.
FPRD-T30Every capacity-witnessed fixed-envelope recoding induces a constant length injective homomorphism tau that sends each matching source pair to reversed matching envelope blocks, preserves and reflects Dyck membership on encoded words, and commutes with the fixed projection readout; for every source trace language K, direct block readout of K and fixed projection readout of tau of K have identical exact suffix behaviors, and whenever source languages K and H agree through floor of N over m, their decoded output suffix behaviors agree through length N.Written-proof claiminformal proofEvidence and limits →Automata and formal languagesFormal languages and scaffolding automataOPEN_PROBLEMS.mdFPRD-D16FPRD governed claims ledgerReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Audit the proof against its dependencies and publish a self-contained evidence summary before increasing maturity.
FPRD-T31For every finite complete source controller, the fixed-envelope recoder constructs a finite complete deterministic trie controller recognizing exactly its tau image, sending malformed blocks and unused envelope symbols to a rejecting sink; intersection with envelope Dyck geometry then equals the tau image of the source Dyck-control intersection, so the abstract M18 theorem supplies one exact decoded suffix dynamic with same-index envelope reconstruction and the block-scaled source observation modulus, while every instance admitted by an explicit finite one-character codec is conjugately realized by the executable M18 implementation.Written-proof claiminformal proofEvidence and limits →Automata and formal languagesFormal languages and scaffolding automataOPEN_PROBLEMS.mdFPRD-D16; FPRD-T28; FPRD-T30FPRD governed claims ledgerReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Audit the proof against its dependencies and publish a self-contained evidence summary before increasing maturity.
FPRD-T32For every injective width-m block code and finite complete source controller, the compiled boundary macro-actions are conjugate to the source actions, the right language at each boundary is exactly the code image of the corresponding source right language, and source residual equality is equivalent to boundary residual equality; bounded future-language and full suffix-lift partitions correspond exactly by N maps to floor of N over m, shortest distinguishing lengths multiply by m, and the source residual dynamic embeds into the image residual dynamic under the encoded macro-actions.Written-proof claiminformal proofEvidence and limits →Automata and formal languagesFormal languages and scaffolding automataOPEN_PROBLEMS.mdFPRD-D17; FPRD-T22; FPRD-T31FPRD governed claims ledgerReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Audit the proof against its dependencies and publish a self-contained evidence summary before increasing maturity.
FPRD-T33The fixed-block compiler allocates exactly one sink plus one boundary and one state for every distinct nonempty proper code prefix at every source state, has the corresponding exact reachable-state and transition counts, transports every surjective source-controller quotient functorially, and preserves source residual count as a lower bound on image residual count; for the fixed envelope, q at most j to the m is exactly the positional-code capacity condition, yielding explicit minimal width or base, envelope-size, trie-overhead, residual, and observation-lag coordinates.Written-proof claiminformal proofEvidence and limits →Automata and formal languagesFormal languages and scaffolding automataOPEN_PROBLEMS.mdFPRD-D17; FPRD-T22; FPRD-T31; FPRD-T32FPRD governed claims ledgerReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Audit the proof against its dependencies and publish a self-contained evidence summary before increasing maturity.
FPRD-T95If the source and cover carriers of an FPRD-T94 stationary principal derivative cover are finite and its frontier language is X, then X reversed belongs to PEL. Equivalently, to obtain a PEG for L by this route, construct the finite stationary cover for L reversed.Written-proof claiminformal proofEvidence and limits →Automata and formal languagesFormal languages and scaffolding automatadocs/notes/stationary-principal-derivative-cover-proof.mdFPRD-T94FPRD governed claims ledgerReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Audit the proof against its dependencies and publish a self-contained evidence summary before increasing maturity.
FPRD-T97Let a deterministic visible-stack language have a complete family of a fixed positive finite number of causal resolvers. If the input, visible control, stack alphabet, resolver control, and family are finite, and X is the resulting forgotten-action projection, then X reversed belongs to PEL.Written-proof claiminformal proofEvidence and limits →Automata and formal languagesFormal languages and scaffolding automatadocs/notes/finite-causal-resolver-cover-proof.mdFPRD-T96FPRD governed claims ledgerReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Audit the proof against its dependencies and publish a self-contained evidence summary before increasing maturity.
FPRD-T99Let a deterministic visible-stack language have a complete family of a fixed positive finite number of lawful finalizable delayed resolvers, with finite input, visible-control, stack, resolver-control, and family carriers. Each branch has a deterministic PDA realization: a right endmarker may drain finish explicitly, and a finite augmented top-window construction eliminates that marker by predicting the same final readout. The projected language is therefore a finite union of DCFLs and belongs to PEL by Rubtsov--Chudinov Theorem 10, with complete-match semantics and no reversal.Written-proof claiminformal proofEvidence and limits →Automata and formal languagesFormal languages and scaffolding automatadocs/notes/finalizable-delayed-resolver-cover-proof.mdFPRD-T98FPRD governed claims ledgerReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Audit the proof against its dependencies and publish a self-contained evidence summary before increasing maturity.
FPRD-D09A finite conventional context-free grammar has finite disjoint terminal and nonterminal sets, finitely many productions, and a distinguished start nonterminal; its canonical relational translation maps terminals to relational terminal actions, nonterminal occurrences to uniquely labeled calls, concatenation to sequence, alternatives to commutative union, epsilon to identity, and an absent production set to failure.DefinitiondefinitionEvidence and limits →Automata and formal languagesFormal languages and scaffolding automatadocs/specs/m13-cfg-relational-lift.mdFPRD-D03; FPRD-D07; FPRD-D08FPRD governed claims ledgerReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Add a self-contained definition page with examples, nonexamples, and dependency boundaries.
FPRD-D10The finite distributive word normal form of a positive relational term maps failure to no words, identity to the empty word, terminals and calls to singleton words, union to finite set union, and sequence to finite word concatenation; for labeled presentations, an annotated enrichment records the finite origin relation from canonical normalized call occurrences to source call labels.DefinitiondefinitionEvidence and limits →Automata and formal languagesFormal languages and scaffolding automatadocs/specs/m14-cfg-normal-form.mdFPRD-D03; FPRD-D07; FPRD-D08; FPRD-D09FPRD governed claims ledgerReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Add a self-contained definition page with examples, nonexamples, and dependency boundaries.
FPRD-D11The suffix-recognition lift Lambda maps a language L to the set-valued suffix behavior that returns every v for which the input factors as xv with x in L; complete-match readout recovers L, and the lift is intended to preserve empty language, epsilon, union, and language concatenation as relational failure, identity, union, and composition.DefinitiondefinitionEvidence and limits →Automata and formal languagesFormal languages and scaffolding automatadocs/specs/m15-classical-regular-dynamics.mdFPRD-D01; FPRD-D02; FPRD-D06FPRD governed claims ledgerReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Add a self-contained definition page with examples, nonexamples, and dependency boundaries.
FPRD-D12The residual recognition dynamic of a language L has the left residuals u-inverse L as states, one-letter left differentiation as its named input actions, L as its distinguished state, empty-word membership as output, and agreement on continuations of length at most N as its bounded observational equivalence.DefinitiondefinitionEvidence and limits →Automata and formal languagesFormal languages and scaffolding automatadocs/specs/m15-classical-regular-dynamics.mdFPRD-D01; FPRD-D02; FPRD-D11FPRD governed claims ledgerReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Add a self-contained definition page with examples, nonexamples, and dependency boundaries.
FPRD-D13A finite Greibach recognition presentation is the canonical labeled relational translation of a finite context-free grammar whose productions have the form A to terminal-a followed by a finite word of nonterminals, or A to epsilon; it retains the finite language and suffix equation operators, labeled call-context actions, bounded restrictions, and remaining-suffix and complete-match readouts.DefinitiondefinitionEvidence and limits →Automata and formal languagesFormal languages and scaffolding automatadocs/specs/m16-greibach-recognition-dynamics.mdFPRD-D06; FPRD-D07; FPRD-D08; FPRD-D09; FPRD-D11FPRD governed claims ledgerReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Add a self-contained definition page with examples, nonexamples, and dependency boundaries.
FPRD-D14The delay profile of a finite positive relational recognition presentation assigns each variable occurrence its guaranteed consumed prefix length, collects the minima in a min-plus dependency matrix, and calls the presentation cycle-guarded when its zero-delay dependency graph is acyclic, equivalently when every dependency cycle has positive total delay.DefinitiondefinitionEvidence and limits →Automata and formal languagesFormal languages and scaffolding automatadocs/specs/m17-delay-graph-guardedness.mdFPRD-D02; FPRD-D06; FPRD-D07FPRD governed claims ledgerReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Add a self-contained definition page with examples, nonexamples, and dependency boundaries.
FPRD-D15A generalized Dyck-control recognition presentation consists of a finite alphabet of matching brackets and neutral symbols, a finite complete DFA on that alphabet, the finite state-pair equation system recognizing well-nested DFA runs, a distinguished union over final states, and a total letter-to-letter map whose decoded observation returns every suffix remaining after an encoded trace prefix.DefinitiondefinitionEvidence and limits →Automata and formal languagesFormal languages and scaffolding automatadocs/specs/m18-universal-dyck-control.mdFPRD-D06; FPRD-D09; FPRD-D11; FPRD-D12; FPRD-D14FPRD governed claims ledgerReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Add a self-contained definition page with examples, nonexamples, and dependency boundaries.
FPRD-D16A capacity-witnessed fixed-envelope recoding consists of a nonempty finite output alphabet Sigma, a positive block width m, a base j at least two, a finite matched source-bracket alphabet with at most j to the m pair types, one m-letter output block for each source bracket, and one distinct m-digit code for each matched pair; its envelope alphabet has symbols (polarity, current output, mate output, digit), matches by reversing polarity and the two output fields, reads the current output field, and replaces each source bracket by one length-m envelope block.DefinitiondefinitionEvidence and limits →Automata and formal languagesFormal languages and scaffolding automatadocs/specs/m19-fixed-envelope-recoding.mdFPRD-D15FPRD governed claims ledgerReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Add a self-contained definition page with examples, nonexamples, and dependency boundaries.
FPRD-D17The fixed-block boundary residual profile of an injective uniform code tau and a finite complete source controller records each source-state right language and its compiled boundary right language, their exact and bounded suffix-lift observations, shortest separation depths, the distinct proper code-prefix counts, raw and reachable compiled-control sizes, and, for a fixed-envelope witness, the digit capacity, envelope size, and block-width observation lag.DefinitiondefinitionEvidence and limits →Automata and formal languagesFormal languages and scaffolding automatadocs/specs/m20-fixed-block-residual-profile.mdFPRD-D11; FPRD-D12; FPRD-D16FPRD governed claims ledgerReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Add a self-contained definition page with examples, nonexamples, and dependency boundaries.
FPRD-C02There exists a deterministic visibly pushdown language whose call, return, and local annotations forget to a language outside PEL. Forgotten-action deterministic visible projections are exactly CFL by FPRD-T91, while Kim and Park exhibit a linear context-free language outside PEG. The universal question is therefore resolved negatively.Source verificationsource verifiedEvidence and limits →Automata and formal languagesFormal languages and scaffolding automatadocs/specs/post-m33-dyck-annotation-forgetting.mdFPRD-T91; FPRD-T92; FPRD-T93; FPRD-T94; FPRD-T95; FPRD-T96; FPRD-T97; FPRD-T98; FPRD-T99; FPRD-T88; FPRD-T100; FPRD-T101; FPRD-T102; FPRD-T103; FPRD-T104; FPRD-T105; FPRD-T106; FPRD-T107; FPRD-T108; FPRD-T109; FPRD-T112; FPRD-T164; FPRD-T165; Kim-Park 2026, Theorem 4.19FPRD governed claims ledgerReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Add the exact primary-source locator and keep source verification separate from proof of the FPRD consequence.
PUB-persistent-stacks-scaffolding--thm-transfer-introTheorem 1.1 (Real-time transfer). Let LL be recognized by a finite deterministic strict real-time multitape Turing machine with a fixed positive number of ordinary single-head work tapes. The machine receives one input symbol and makes one global transition per step, has no input-length advice, and performs no post-input computation. Then LR∈PEG.L^R\in\mathsf{PEG}.theoremreleased publication statement; not independently promoted by this indexEvidence and limits →Automata and formal languagesScaffolding automata and PEGsReal-time multitape languages transfer to parsing expression grammars, Theorem 1.1Theorem-level dependency graph not yet atomizedReal-time multitape languages transfer to parsing expression grammarsReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Map this publication statement to any governed claim, verify its hypotheses and proof dependencies, and remove duplicate inventory rows only after an exact mapping exists.
PUB-persistent-stacks-scaffolding--cor-epal-introCorollary 1.2 . EPAL2∈PEG\mathsf{EPAL}_2\in\mathsf{PEG} . Hence Conjecture 7 of Loff–Moreira–Reis is false.corollaryreleased publication statement; not independently promoted by this indexEvidence and limits →Automata and formal languagesScaffolding automata and PEGsReal-time multitape languages transfer to parsing expression grammars, Corollary 1.2Theorem-level dependency graph not yet atomizedReal-time multitape languages transfer to parsing expression grammarsReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Map this publication statement to any governed claim, verify its hypotheses and proof dependencies, and remove duplicate inventory rows only after an exact mapping exists.
PUB-persistent-stacks-scaffolding--thm-lmrTheorem 2.1 (Loff–Moreira–Reis). For every language KK , K∈PEG⟺KR is decided by a scaffolding automaton.K\in\mathsf{PEG} \quad\Longleftrightarrow\quad K^R\text{ is decided by a scaffolding automaton}.theoremreleased publication statement; not independently promoted by this indexEvidence and limits →Automata and formal languagesScaffolding automata and PEGsReal-time multitape languages transfer to parsing expression grammars, Theorem 2.1Theorem-level dependency graph not yet atomizedReal-time multitape languages transfer to parsing expression grammarsReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Map this publication statement to any governed claim, verify its hypotheses and proof dependencies, and remove duplicate inventory rows only after an exact mapping exists.
PUB-persistent-stacks-scaffolding--lem-fresh-initialLemma 2.2 (Fresh initial state). Every finite scaffolding automaton AA has an equivalent finite scaffolding automaton A⋆A^\star whose initial state occurs only before the first input symbol. The construction preserves acceptance of the empty word and every nonempty word without inserting an input step.lemmareleased publication statement; not independently promoted by this indexEvidence and limits →Automata and formal languagesScaffolding automata and PEGsReal-time multitape languages transfer to parsing expression grammars, Lemma 2.2Theorem-level dependency graph not yet atomizedReal-time multitape languages transfer to parsing expression grammarsReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Map this publication statement to any governed claim, verify its hypotheses and proof dependencies, and remove duplicate inventory rows only after an exact mapping exists.
PUB-persistent-stacks-scaffolding--lem-stack-updateLemma 3.1 (Persistent-stack update). Suppose the old scaffold is strictly backward and satisfies CleanEmpty\mathsf{CleanEmpty} . After appending the node specified by the table, the decoded stack at v+v^+ is exactly the result of the selected stack operation. The new scaffold is strictly backward and again satisfies CleanEmpty\mathsf{CleanEmpty} .lemmareleased publication statement; not independently promoted by this indexEvidence and limits →Automata and formal languagesScaffolding automata and PEGsReal-time multitape languages transfer to parsing expression grammars, Lemma 3.1Theorem-level dependency graph not yet atomizedReal-time multitape languages transfer to parsing expression grammarsReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Map this publication statement to any governed claim, verify its hypotheses and proof dependencies, and remove duplicate inventory rows only after an exact mapping exists.
PUB-persistent-stacks-scaffolding--thm-parallel-stacksTheorem 3.2 (Parallel persistent stacks). Every deterministic letter-synchronous finite-control machine with a fixed positive number ss of stacks, performing at most one push, keep, or pop per stack and per input symbol, is simulated exactly by a degree- ss , distance-two scaffolding automaton.theoremreleased publication statement; not independently promoted by this indexEvidence and limits →Automata and formal languagesScaffolding automata and PEGsReal-time multitape languages transfer to parsing expression grammars, Theorem 3.2Theorem-level dependency graph not yet atomizedReal-time multitape languages transfer to parsing expression grammarsReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Map this publication statement to any governed claim, verify its hypotheses and proof dependencies, and remove duplicate inventory rows only after an exact mapping exists.
PUB-persistent-stacks-scaffolding--lem-zipperLemma 4.1 (Tape zipper). Every strict real-time mm -tape machine is simulated letter-for-letter by a finite-control machine with 2m2m stacks, performing at most one push, keep, or pop on each stack per input symbol.lemmareleased publication statement; not independently promoted by this indexEvidence and limits →Automata and formal languagesScaffolding automata and PEGsReal-time multitape languages transfer to parsing expression grammars, Lemma 4.1Theorem-level dependency graph not yet atomizedReal-time multitape languages transfer to parsing expression grammarsReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Map this publication statement to any governed claim, verify its hypotheses and proof dependencies, and remove duplicate inventory rows only after an exact mapping exists.
PUB-persistent-stacks-scaffolding--thm-machine-scaffoldTheorem 4.2 (Strict machine-to-scaffold simulation). Let MM be a strict real-time mm -tape machine, m≥1m\geq 1 . There is a scaffolding automaton AMA_M of degree 2m2m and distance two such that L(AM)=L(M).L(A_M)=L(M). After every input prefix, the two persistent stacks associated with each tape, together with its scanned symbol in finite control, reconstruct the source tape exactly. In particular, the reconstructed and source tapes agree at every integer offset from the head, including their implicit blank tails, and the source control states agree.theoremreleased publication statement; not independently promoted by this indexEvidence and limits →Automata and formal languagesScaffolding automata and PEGsReal-time multitape languages transfer to parsing expression grammars, Theorem 4.2Theorem-level dependency graph not yet atomizedReal-time multitape languages transfer to parsing expression grammarsReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Map this publication statement to any governed claim, verify its hypotheses and proof dependencies, and remove duplicate inventory rows only after an exact mapping exists.
PUB-persistent-stacks-scaffolding--thm-transferTheorem 5.1 . If LL is recognized by a strict real-time multitape machine, then LR∈PEG.L^R\in\mathsf{PEG}. Equivalently, rev(RT-MTTM)⊆PEG.\mathsf{rev}(\mathsf{RT\text{-}MTTM})\subseteq\mathsf{PEG}.theoremreleased publication statement; not independently promoted by this indexEvidence and limits →Automata and formal languagesScaffolding automata and PEGsReal-time multitape languages transfer to parsing expression grammars, Theorem 5.1Theorem-level dependency graph not yet atomizedReal-time multitape languages transfer to parsing expression grammarsReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Map this publication statement to any governed claim, verify its hypotheses and proof dependencies, and remove duplicate inventory rows only after an exact mapping exists.
PUB-persistent-stacks-scaffolding--lem-strict-onlineLemma 5.2 (Strict real time is online constant time). Every language recognized by a strict real-time multitape machine belongs to Online(O(1))\mathsf{Online}(O(1)) in the sense of Loff–Moreira–Reis Definition 22.lemmareleased publication statement; not independently promoted by this indexEvidence and limits →Automata and formal languagesScaffolding automata and PEGsReal-time multitape languages transfer to parsing expression grammars, Lemma 5.2Theorem-level dependency graph not yet atomizedReal-time multitape languages transfer to parsing expression grammarsReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Map this publication statement to any governed claim, verify its hypotheses and proof dependencies, and remove duplicate inventory rows only after an exact mapping exists.
PUB-persistent-stacks-scaffolding--cor-properCorollary 5.3 (Proper class containment). rev(RT-MTTM)⊊PEG.\mathsf{rev}(\mathsf{RT\text{-}MTTM})\subsetneq\mathsf{PEG}.corollaryreleased publication statement; not independently promoted by this indexEvidence and limits →Automata and formal languagesScaffolding automata and PEGsReal-time multitape languages transfer to parsing expression grammars, Corollary 5.3Theorem-level dependency graph not yet atomizedReal-time multitape languages transfer to parsing expression grammarsReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Map this publication statement to any governed claim, verify its hypotheses and proof dependencies, and remove duplicate inventory rows only after an exact mapping exists.
PUB-persistent-stacks-scaffolding--thm-classical-pal-interfaceTheorem 6.1 (Classical palindrome interface (classical, imported)). There are finite m,Q,Tm,Q,T and a total strict real-time mm -tape machine PP such that, for every x∈{0,1}∗x\in\{0,1\}^* , the state reached after exactly ∣x∣|x| transitions is accepting if and only if x=xRx=x^R . The statement includes x=εx=\varepsilon : the initial state is accepting.theoremreleased publication statement; not independently promoted by this indexEvidence and limits →Automata and formal languagesScaffolding automata and PEGsReal-time multitape languages transfer to parsing expression grammars, Theorem 6.1Theorem-level dependency graph not yet atomizedReal-time multitape languages transfer to parsing expression grammarsReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Map this publication statement to any governed claim, verify its hypotheses and proof dependencies, and remove duplicate inventory rows only after an exact mapping exists.
PUB-persistent-stacks-scaffolding--lem-epal-identityLemma 6.2 (Even-palindrome identity). For every binary word xx , x∈{wwR:w∈{0,1}∗}⟺x=xR  and  ∣x∣ is even.x\in\{ww^R:w\in\{0,1\}^*\} \quad\Longleftrightarrow\quad x=x^R\ \text{ and }\ |x|\text{ is even}. The equivalence includes x=εx=\varepsilon .lemmareleased publication statement; not independently promoted by this indexEvidence and limits →Automata and formal languagesScaffolding automata and PEGsReal-time multitape languages transfer to parsing expression grammars, Lemma 6.2Theorem-level dependency graph not yet atomizedReal-time multitape languages transfer to parsing expression grammarsReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Map this publication statement to any governed claim, verify its hypotheses and proof dependencies, and remove duplicate inventory rows only after an exact mapping exists.
PUB-persistent-stacks-scaffolding--lem-epal-reversalLemma 6.3 (Reversal invariance). (EPAL2)R=EPAL2.(\mathsf{EPAL}_2)^R=\mathsf{EPAL}_2.lemmareleased publication statement; not independently promoted by this indexEvidence and limits →Automata and formal languagesScaffolding automata and PEGsReal-time multitape languages transfer to parsing expression grammars, Lemma 6.3Theorem-level dependency graph not yet atomizedReal-time multitape languages transfer to parsing expression grammarsReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Map this publication statement to any governed claim, verify its hypotheses and proof dependencies, and remove duplicate inventory rows only after an exact mapping exists.
PUB-persistent-stacks-scaffolding--lem-parity-productLemma 6.4 (Parity product). Suppose a strict real-time machine PP reports after every prefix xx , including the empty prefix, whether x=xRx=x^R . Then a strict real-time machine PevenP_{\mathrm{even}} recognizes exactly EPAL2\mathsf{EPAL}_2 .lemmareleased publication statement; not independently promoted by this indexEvidence and limits →Automata and formal languagesScaffolding automata and PEGsReal-time multitape languages transfer to parsing expression grammars, Lemma 6.4Theorem-level dependency graph not yet atomizedReal-time multitape languages transfer to parsing expression grammarsReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Map this publication statement to any governed claim, verify its hypotheses and proof dependencies, and remove duplicate inventory rows only after an exact mapping exists.
PUB-persistent-stacks-scaffolding--thm-epalTheorem 6.5 . The even-length binary palindrome language has a parsing expression grammar: EPAL2={wwR:w∈{0,1}∗}∈PEG.\boxed{\mathsf{EPAL}_2=\{ww^R:w\in\{0,1\}^*\}\in\mathsf{PEG}.}theoremreleased publication statement; not independently promoted by this indexEvidence and limits →Automata and formal languagesScaffolding automata and PEGsReal-time multitape languages transfer to parsing expression grammars, Theorem 6.5Theorem-level dependency graph not yet atomizedReal-time multitape languages transfer to parsing expression grammarsReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Map this publication statement to any governed claim, verify its hypotheses and proof dependencies, and remove duplicate inventory rows only after an exact mapping exists.
PUB-persistent-stacks-scaffolding--siteauto-main-tex-19Corollary 6.6 . Conjecture 7 of Loff, Moreira, and Reis [4] is false.corollaryreleased publication statement; not independently promoted by this indexEvidence and limits →Automata and formal languagesScaffolding automata and PEGsReal-time multitape languages transfer to parsing expression grammars, Corollary 6.6Theorem-level dependency graph not yet atomizedReal-time multitape languages transfer to parsing expression grammarsReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Map this publication statement to any governed claim, verify its hypotheses and proof dependencies, and remove duplicate inventory rows only after an exact mapping exists.
PUB-direct-palindrome-scaffolding--thm-lmrTheorem 2.7 (Loff–Moreira–Reis [7, Theorem 16, p. 21] ). A language L⊆Σ∗L\subseteq\Sigma^* is in PEG\mathsf{PEG} if and only if its reversal LRL^R is decided by some scaffolding automaton. In particular, if a finite scaffolding automaton decides LL , then LRL^R is recognized by a total complete-match PEG.theoremreview publication statement; not independently promoted by this indexEvidence and limits →Automata and formal languagesScaffolding automata and PEGsPersistent receipts and simultaneous records: a direct scaffold for even palindromes, Theorem 2.7Theorem-level dependency graph not yet atomizedPersistent receipts and simultaneous records: a direct scaffold for even palindromesReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Map this publication statement to any governed claim, verify its hypotheses and proof dependencies, and remove duplicate inventory rows only after an exact mapping exists.
PUB-direct-palindrome-scaffolding--thm-contextTheorem 5.4 (Occurrence-context factorization). After reading aa , the new longest even suffix P′P' and reversed context ℓ′\ell' are exactly (P′,ℓ′)={(aPa,ℓ0),ℓ=aℓ0,(aDa(P)a,ωa(P)ℓ),ℓ∉aΣ∗, Da(P) defined,(ϵ,aPℓ),ℓ∉aΣ∗, Da(P) undefined.(P',\ell')= \begin{cases} (aPa,\ell_0), &\ell=a\ell_0,\\[1mm] (aD_a(P)a,\omega_a(P)\ell), &\ell\notin a\Sigma^*,\ D_a(P)\text{ defined},\\[1mm] (\epsilon,aP\ell), &\ell\notin a\Sigma^*,\ D_a(P)\text{ undefined}. \end{cases} Moreover, S∈EPAL2⟺ℓ=ϵ.S\in\mathsf{EPAL}_2\quad\Longleftrightarrow\quad \ell=\epsilon.theoremreview publication statement; not independently promoted by this indexEvidence and limits →Automata and formal languagesScaffolding automata and PEGsPersistent receipts and simultaneous records: a direct scaffold for even palindromes, Theorem 5.4Theorem-level dependency graph not yet atomizedPersistent receipts and simultaneous records: a direct scaffold for even palindromesReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Map this publication statement to any governed claim, verify its hypotheses and proof dependencies, and remove duplicate inventory rows only after an exact mapping exists.
PUB-direct-palindrome-scaffolding--lem-chunkLemma 5.6 (chunk recursion). Let PP be a nonempty even palindrome with suffix link L=λ(P)L=\lambda(P) , bridge bb , and bridge block BPB_P . Then Db(P)=L,ωb(P)=BP,D_b(P)=L,\qquad \omega_b(P)=B_P, and for every letter a≠ba\ne b , Da(P)=Da(L),ωa(P)=ωa(L) b BP,D_a(P)=D_a(L),\qquad \omega_a(P)=\omega_a(L)\,b\,B_P, with the same definedness on both sides (for L=ϵL=\epsilon the right-hand sides are undefined).lemmareview publication statement; not independently promoted by this indexEvidence and limits →Automata and formal languagesScaffolding automata and PEGsPersistent receipts and simultaneous records: a direct scaffold for even palindromes, Lemma 5.6Theorem-level dependency graph not yet atomizedPersistent receipts and simultaneous records: a direct scaffold for even palindromesReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Map this publication statement to any governed claim, verify its hypotheses and proof dependencies, and remove duplicate inventory rows only after an exact mapping exists.
PUB-direct-palindrome-scaffolding--thm-mirrorTheorem 6.1 (Typed mirror receipt). Suppose an update selects a longest suffix occurrence QQ of the old input that is immediately preceded by aa , and creates Y=aQaY=aQa . Then λ(Y)={aDa(Q)a,Da(Q) defined,ϵ,Da(Q) undefined.\lambda(Y)= \begin{cases} aD_a(Q)a,&D_a(Q)\text{ defined},\\ \epsilon,&D_a(Q)\text{ undefined}. \end{cases} The palindrome λ(Y)\lambda(Y) has a complete occurrence in the old input and a pre-existing birth record. One old typed pointer can therefore install the suffix-link field of YY .theoremreview publication statement; not independently promoted by this indexEvidence and limits →Automata and formal languagesScaffolding automata and PEGsPersistent receipts and simultaneous records: a direct scaffold for even palindromes, Theorem 6.1Theorem-level dependency graph not yet atomizedPersistent receipts and simultaneous records: a direct scaffold for even palindromesReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Map this publication statement to any governed claim, verify its hypotheses and proof dependencies, and remove duplicate inventory rows only after an exact mapping exists.
PUB-direct-palindrome-scaffolding--prop-endpointProposition 6.2 (Endpoint-only escape). For m≥2m\ge2 , let Sm=02m1100S_m=0^{2m}1100 . Its longest even-palindromic suffix is 001100001100 and the suffix link is 0000 . The mirror occurrence of 0000 ends at the historical prefix 02m0^{2m} , whose longest suffix-link chain is 02m,02m−2,…,00,ϵ.0^{2m},0^{2m-2},\ldots,00,\epsilon. Recovering 0000 from that untyped endpoint takes exactly m−1m-1 suffix-link steps.propositionreview publication statement; not independently promoted by this indexEvidence and limits →Automata and formal languagesScaffolding automata and PEGsPersistent receipts and simultaneous records: a direct scaffold for even palindromes, Proposition 6.2Theorem-level dependency graph not yet atomizedPersistent receipts and simultaneous records: a direct scaffold for even palindromesReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Map this publication statement to any governed claim, verify its hypotheses and proof dependencies, and remove duplicate inventory rows only after an exact mapping exists.
PUB-direct-palindrome-scaffolding--prop-type-birthProposition 7.1 (Future transition after type birth). For r≥1r\geq1 , put Ar=02rA_r=0^{2r} , Pr=Ar11Ar,Tr=1Ar1.P_r=A_r11A_r, \qquad T_r=1A_r1. Then D1(Pr)=ArD_1(P_r)=A_r , so the transition selected by 11 has target Tr=1D1(Pr)1T_r=1D_1(P_r)1 . The type PrP_r is born by the end of the prefix PrP_r , but TrT_r is not a factor of that prefix. It becomes available only in a later history such as Pr1PrP_r1P_r . Thus the immutable first-birth record of PrP_r cannot already point to every future transition out of PrP_r .propositionreview publication statement; not independently promoted by this indexEvidence and limits →Automata and formal languagesScaffolding automata and PEGsPersistent receipts and simultaneous records: a direct scaffold for even palindromes, Proposition 7.1Theorem-level dependency graph not yet atomizedPersistent receipts and simultaneous records: a direct scaffold for even palindromesReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Map this publication statement to any governed claim, verify its hypotheses and proof dependencies, and remove duplicate inventory rows only after an exact mapping exists.
PUB-direct-palindrome-scaffolding--prop-anchor-dependenceProposition 7.2 (Anchor dependence). For the fixed one-letter block w=0w=0 and anchors Ar=02rA_r=0^{2r} , λ(0Ar0)=Ar.\lambda(0A_r0)=A_r. Consequently the same raw rope cell 00 requires infinitely many distinct typed receipt targets as its anchor varies.propositionreview publication statement; not independently promoted by this indexEvidence and limits →Automata and formal languagesScaffolding automata and PEGsPersistent receipts and simultaneous records: a direct scaffold for even palindromes, Proposition 7.2Theorem-level dependency graph not yet atomizedPersistent receipts and simultaneous records: a direct scaffold for even palindromesReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Map this publication statement to any governed claim, verify its hypotheses and proof dependencies, and remove duplicate inventory rows only after an exact mapping exists.
PUB-direct-palindrome-scaffolding--prop-bridge-chaseProposition 7.3 (Bridge-chasing escape). For r≥1r\geq1 and d≥0d\geq0 , let Pr,d=Ar(11Ar)d,Ar=02r.P_{r,d}=A_r(11A_r)^d, \qquad A_r=0^{2r}. These are even palindromes. For d>0d>0 , λ(Pr,d)=Pr,d−1andbPr,d=1,\lambda(P_{r,d})=P_{r,d-1} \quad\text{and}\quad b_{P_{r,d}}=1, whereas the bridge of ArA_r is 00 . The search for the 00 -transition from Pr,dP_{r,d} therefore makes exactly dd failed bridge tests before reaching the variable target ArA_r .propositionreview publication statement; not independently promoted by this indexEvidence and limits →Automata and formal languagesScaffolding automata and PEGsPersistent receipts and simultaneous records: a direct scaffold for even palindromes, Proposition 7.3Theorem-level dependency graph not yet atomizedPersistent receipts and simultaneous records: a direct scaffold for even palindromesReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Map this publication statement to any governed claim, verify its hypotheses and proof dependencies, and remove duplicate inventory rows only after an exact mapping exists.
PUB-direct-palindrome-scaffolding--lem-shadowLemma 8.3 (Bridge-shadow identity). Suppose H=RbPH=RbP , λ(H)=P\lambda(H)=P , and PP is the longest even-palindromic suffix of wRPw^RP . If w=ϵw=\epsilon , or if the first letter of ww differs from bb , then Λ(H,w)=Λ(P,w).\Lambda(H,w)=\Lambda(P,w).lemmareview publication statement; not independently promoted by this indexEvidence and limits →Automata and formal languagesScaffolding automata and PEGsPersistent receipts and simultaneous records: a direct scaffold for even palindromes, Lemma 8.3Theorem-level dependency graph not yet atomizedPersistent receipts and simultaneous records: a direct scaffold for even palindromesReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Map this publication statement to any governed claim, verify its hypotheses and proof dependencies, and remove duplicate inventory rows only after an exact mapping exists.
PUB-direct-palindrome-scaffolding--lem-mirror-prefixLemma 8.5 (Mirror-prefix lemma). Let YY be a nonempty even palindrome and cc a letter. If Dc(Y)D_c(Y) is defined, the final palindrome of Π(cDc(Y)c,ωc(Y))\Pi(cD_c(Y)c,\omega_c(Y)) is F=Yc ωc(Y)F=Yc\,\omega_c(Y) , and λ(F)=Y\lambda(F)=Y . If Dc(Y)D_c(Y) is undefined, the final palindrome of Π(ϵ,cY)\Pi(\epsilon,cY) is F=YccYF=YccY , and λ(F)=Y\lambda(F)=Y . In both cases the last receipt of the rope is the anchor’s source YY itself.lemmareview publication statement; not independently promoted by this indexEvidence and limits →Automata and formal languagesScaffolding automata and PEGsPersistent receipts and simultaneous records: a direct scaffold for even palindromes, Lemma 8.5Theorem-level dependency graph not yet atomizedPersistent receipts and simultaneous records: a direct scaffold for even palindromesReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Map this publication statement to any governed claim, verify its hypotheses and proof dependencies, and remove duplicate inventory rows only after an exact mapping exists.
PUB-direct-palindrome-scaffolding--cor-anchor-linksCorollary 8.6 . With Y=LbBY=LbB as above and c≠bc\ne b : if Dc(Y)D_c(Y) is defined, write L=ZcDc(L)L=ZcD_c(L) ; then λ(ZcL)=L\lambda(ZcL)=L . If Dc(Y)D_c(Y) is undefined, then λ(LccL)=L\lambda(LccL)=L .corollaryreview publication statement; not independently promoted by this indexEvidence and limits →Automata and formal languagesScaffolding automata and PEGsPersistent receipts and simultaneous records: a direct scaffold for even palindromes, Corollary 8.6Theorem-level dependency graph not yet atomizedPersistent receipts and simultaneous records: a direct scaffold for even palindromesReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Map this publication statement to any governed claim, verify its hypotheses and proof dependencies, and remove duplicate inventory rows only after an exact mapping exists.
PUB-direct-palindrome-scaffolding--thm-ropesTheorem 8.7 (Receipt-rope recurrence). Let ρb\rho_b be the header receipt of Ωb(Y)\Omega_b(Y) . For c≠bc\ne b , Ωc(Y)={undefined,Ωc(L) undefined,Ωc(L)⋅(b,ρb)⋅body⁡Ωb(Y),otherwise,\Omega_c(Y)= \begin{cases} \text{undefined},&\Omega_c(L)\text{ undefined},\\ \Omega_c(L)\cdot(b,\rho_b)\cdot\operatorname{body}\Omega_b(Y),&\text{otherwise}, \end{cases} and, whenever Zc(Y)Z_c(Y) is defined, Zc(Y)=Zc(L)⋅(b,ρb)⋅body⁡Ωb(Y).Z_c(Y)=Z_c(L)\cdot(b,\rho_b)\cdot\operatorname{body}\Omega_b(Y).theoremreview publication statement; not independently promoted by this indexEvidence and limits →Automata and formal languagesScaffolding automata and PEGsPersistent receipts and simultaneous records: a direct scaffold for even palindromes, Theorem 8.7Theorem-level dependency graph not yet atomizedPersistent receipts and simultaneous records: a direct scaffold for even palindromesReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Map this publication statement to any governed claim, verify its hypotheses and proof dependencies, and remove duplicate inventory rows only after an exact mapping exists.
PUB-direct-palindrome-scaffolding--thm-closureTheorem 8.9 (Full abstract receipt closure). Over a fixed alphabet, a fresh occurrence record, its complete direct/reset rope table, and the updated live context are obtained from old receipts by a fixed number of head, tail, singleton, inject, and catenation operations.theoremreview publication statement; not independently promoted by this indexEvidence and limits →Automata and formal languagesScaffolding automata and PEGsPersistent receipts and simultaneous records: a direct scaffold for even palindromes, Theorem 8.9Theorem-level dependency graph not yet atomizedPersistent receipts and simultaneous records: a direct scaffold for even palindromesReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Map this publication statement to any governed claim, verify its hypotheses and proof dependencies, and remove duplicate inventory rows only after an exact mapping exists.
PUB-direct-palindrome-scaffolding--thm-compilerTheorem 10.2 (Simultaneous batch compiler). Every transducer of Definition 10.1 whose initial record graph is fixed, finite, immutable, and pointer-closed compiles exactly and letter-synchronously into a finite scaffolding automaton of degree d=max⁡{1,s+Aq}d=\max\{1,s+Aq\} and observation/update distance at most r+1r+1 . The source transition uses only bounded labelled rooted unfoldings and does not branch on pointer identity; acceptance is in finite control.theoremreview publication statement; not independently promoted by this indexEvidence and limits →Automata and formal languagesScaffolding automata and PEGsPersistent receipts and simultaneous records: a direct scaffold for even palindromes, Theorem 10.2Theorem-level dependency graph not yet atomizedPersistent receipts and simultaneous records: a direct scaffold for even palindromesReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Map this publication statement to any governed claim, verify its hypotheses and proof dependencies, and remove duplicate inventory rows only after an exact mapping exists.
PUB-direct-palindrome-scaffolding--thm-ktTheorem 11.1 (Kaplan–Tarjan [6, Theorem 5.1, p. 592] ). There is a purely functional regular catenable steque whose push, pop, inject, and catenation operations take worst-case constant time and preserve the representation.theoremreview publication statement; not independently promoted by this indexEvidence and limits →Automata and formal languagesScaffolding automata and PEGsPersistent receipts and simultaneous records: a direct scaffold for even palindromes, Theorem 11.1Theorem-level dependency graph not yet atomizedPersistent receipts and simultaneous records: a direct scaffold for even palindromesReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Map this publication statement to any governed claim, verify its hypotheses and proof dependencies, and remove duplicate inventory rows only after an exact mapping exists.
PUB-direct-palindrome-scaffolding--thm-stagingTheorem 11.2 (Opaque-atom staging). Let a strict purely functional sequence operation, parameterized by a base element type AA , use finite constructor tests and a worst-case bounded number of car\mathsf{car} , cons\mathsf{cons} , and cdr\mathsf{cdr} operations. It may inspect the representation’s own pairs, buffers, and recursive child structures, but it may not inspect, compare, hash, traverse, or identity-test values of the base type AA . With new elements replaced by symbolic atoms, its branch and fresh structural allocation graph are determined by old structure alone. The graph is finite, acyclic, and uniformly bounded. A symbolic element may denote a designated fresh payload record, and a fresh owner may store a fixed tuple of resulting roots. Adding those payload and owner slots to the structural skeleton forms one bounded simultaneous batch. Substitution is sound even when a payload field points back to the owner and creates a cycle.theoremreview publication statement; not independently promoted by this indexEvidence and limits →Automata and formal languagesScaffolding automata and PEGsPersistent receipts and simultaneous records: a direct scaffold for even palindromes, Theorem 11.2Theorem-level dependency graph not yet atomizedPersistent receipts and simultaneous records: a direct scaffold for even palindromesReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Map this publication statement to any governed claim, verify its hypotheses and proof dependencies, and remove duplicate inventory rows only after an exact mapping exists.
PUB-direct-palindrome-scaffolding--thm-whole-client-normalizationTheorem 11.3 (Whole-client bounded symbolic normalization). Fix a finite immutable record signature. Let one deterministic strict client transition have a uniform bound on calls, constructor tests, loops, recursion, and retained fresh records. Suppose it observes only finite tags, finite nonpointer data, old records reached by bounded rooted addresses, and constructors of ordinary fresh structural records already known to its symbolic evaluation. It neither observes pointer identity or allocation state nor inspects an unresolved opaque atom, designated fresh payload, or designated fresh owner. Suppose also that every old pointer later read or retained has a bounded rooted provenance, temporary control packages do not escape, and unreachable failure leaves are completed by a fixed finite plan. Then the whole client normalizes to one bounded simultaneous record-transducer plan determined only by finite control, the input letter, and a bounded labelled unfolding of the old roots.theoremreview publication statement; not independently promoted by this indexEvidence and limits →Automata and formal languagesScaffolding automata and PEGsPersistent receipts and simultaneous records: a direct scaffold for even palindromes, Theorem 11.3Theorem-level dependency graph not yet atomizedPersistent receipts and simultaneous records: a direct scaffold for even palindromesReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Map this publication statement to any governed claim, verify its hypotheses and proof dependencies, and remove duplicate inventory rows only after an exact mapping exists.
PUB-direct-palindrome-scaffolding--thm-directTheorem 12.2 (Direct palindrome construction). For a persistent sequence implementation satisfying the contract of Section 11.1, the receipt construction recognizes the binary even-palindrome language with a finite scaffolding automaton. If the complete client has source-record bounds (A∗,q,R∗)(A_*,q,R_*) , it has degree max⁡{1,2+A∗q}\max\{1,2+A_*q\} and distance at most R∗+1R_*+1 .theoremreview publication statement; not independently promoted by this indexEvidence and limits →Automata and formal languagesScaffolding automata and PEGsPersistent receipts and simultaneous records: a direct scaffold for even palindromes, Theorem 12.2Theorem-level dependency graph not yet atomizedPersistent receipts and simultaneous records: a direct scaffold for even palindromesReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Map this publication statement to any governed claim, verify its hypotheses and proof dependencies, and remove duplicate inventory rows only after an exact mapping exists.
PUB-direct-palindrome-scaffolding--cor-pegCorollary 12.3 (Direct PEG route). Under the sequence contract in Theorem 12.2, the construction yields a PEG for EPAL2\mathsf{EPAL}_2 .corollaryreview publication statement; not independently promoted by this indexEvidence and limits →Automata and formal languagesScaffolding automata and PEGsPersistent receipts and simultaneous records: a direct scaffold for even palindromes, Corollary 12.3Theorem-level dependency graph not yet atomizedPersistent receipts and simultaneous records: a direct scaffold for even palindromesReviewed 2026-09-01No documented external or specialist review of this FPRD result is recorded.Map this publication statement to any governed claim, verify its hypotheses and proof dependencies, and remove duplicate inventory rows only after an exact mapping exists.