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arXiv · 2005.05505

Nice formulas, $xyx$-formulas, and palindrome patterns

Pascal Ochem·Matthieu Rosenfeld
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Abstract

We characterize the formulas that are avoided by every $α$-free word for some $α>1$. We study the avoidability index of formulas whose fragments are of the form $XYX$. The largest avoidability index of an avoidable palindrome pattern is known to be at least $4$ and at most $16$. We make progress toward the conjecture that every avoidable palindrome pattern is $4$-avoidable.

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Pascal Ochem, Matthieu Rosenfeld. 2020-05-12. Nice formulas, $xyx$-formulas, and palindrome patterns. https://arxiv.org/abs/2005.05505

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