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Every binary pattern of length six is avoidable on the two-letter alphabet

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Abstract

U. Schmidt [9, 10] showed that every pattern on two letters of length at least 13 is avoidable an a two-letter alphabet (i.e. 2-avoidable). We prove that this bound can be improved to 6. Since there are patterns of length 5 being not 2-avoidable, this bound is optimal.

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  1. Fachbereich Informatik, Johann Wolfgang Goethe-Universität, W-6000, Frankfurt am Main, Germany

    Peter Roth

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  1. Peter Roth
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Roth, P. Every binary pattern of length six is avoidable on the two-letter alphabet. Acta Informatica 29, 95–107 (1992). https://doi.org/10.1007/BF01178567

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  • DOI: https://doi.org/10.1007/BF01178567

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