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Pattern Avoidability with Involution

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 نشر من قبل EPTCS
 تاريخ النشر 2011
  مجال البحث الهندسة المعلوماتية
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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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