Abstract
We examine avoidable patterns, unavoidable in the sense of Bean, Ehrenfeucht, McNulty. We prove that each pattern on two letters of length at least 13 is avoidable on an alphabet with two letter. The proof is based essentially on two facts: First, each pattern containing an overlapping factor is avoidable by the infinite word of Thue-Morse; secondly, each pattern without overlapping factor is avoidable by the infinite word of Fibonacci.
This article was done while the author stayed at LITP, Université Pierre et Marie Curie, Paris
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© 1987 Springer-Verlag Berlin Heidelberg
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Schmidt, U. (1987). Avoidable patterns on 2 letters. In: Brandenburg, F.J., Vidal-Naquet, G., Wirsing, M. (eds) STACS 87. STACS 1987. Lecture Notes in Computer Science, vol 247. Springer, Berlin, Heidelberg. https://doi.org/10.1007/BFb0039606
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DOI: https://doi.org/10.1007/BFb0039606
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