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arXiv · 1108.3622

Pattern Avoidability with Involution

Bastian Bischoff·Dirk Nowotka
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Abstract

An infinte word w avoids a pattern p with the involution t if there is no substitution for the variables in p and no involution t such that the resulting word is a factor of w. We investigate the avoidance of patterns with respect to the size of the alphabet. For example, it is shown that the pattern a t(a) a can be avoided over three letters but not two letters, whereas it is well known that a a a is avoidable over two letters.

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Bastian Bischoff, Dirk Nowotka. 2011-08-18. Pattern Avoidability with Involution. https://doi.org/10.4204/eptcs.63.10

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