6:T1ae0,

Lemma 8.3 (Bridge-shadow identity). Suppose $H=RbP$ , $\lambda(H)=P$ , and $P$ is the longest even-palindromic suffix of $w^RP$ . If $w=\epsilon$ , or if the first letter of $w$ differs from $b$ , then $\Lambda(H,w)=\Lambda(P,w).$

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