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On the context-freeness of the set of words containing overlaps

Narad Rampersad
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Abstract

We show that the set of binary words containing overlaps is not unambiguously context-free and that the set of ternary words containing overlaps is not context-free. We also show that the set of binary words that are not subwords of the Thue-Morse word is not unambiguously context-free.

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Narad Rampersad. 2006-10-02. On the context-freeness of the set of words containing overlaps. https://arxiv.org/abs/math/0610067

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