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arXiv · 1804.09735

Nyldon words

Émilie Charlier·Manon Philibert·Manon Stipulanti
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Abstract

The Chen-Fox-Lyndon theorem states that every finite word over a fixed alphabet can be uniquely factorized as a lexicographically nonincreasing sequence of Lyndon words. This theorem can be used to define the family of Lyndon words in a recursive way. If the lexicographic order is reversed in this definition, we obtain a new family of words, which are called the Nyldon words. In this paper, we show that every finite word can be uniquely factorized into a lexicographically nondecreasing sequence of Nyldon words. Otherwise stated, Nyldon words form a complete factorization of the free monoid with respect to the decreasing lexicographic order. Then we investigate this new family of words. In particular, we show that Nyldon words form a right Lazard set.

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Émilie Charlier, Manon Philibert, Manon Stipulanti. 2018-04-25. Nyldon words. https://arxiv.org/abs/1804.09735

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