The palindromic length of a nonempty finite word is the least number of nonempty palindromes whose concatenation is . For an infinite word , let be the number of nonempty palindromic prefixes of , and let consist of those prefixes , , whose palindromic length equals the maximum attained among the nonempty prefixes of . We prove the finite inequality for every . In particular, if has infinitely many palindromic prefixes, then The coefficient is optimal, already for a nonconstant periodic word. The proof uses chains of occurrences connected by palindromic factors, together with trimming and reflection arguments that preserve lower bounds on palindromic length.

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