Overlap-free morphisms and finite test-sets
نویسندگان
چکیده
منابع مشابه
Characterization of Test-sets for Overlap-free Morphisms
We give a characterization of all the sets X such that any morphism h on fa; bg is overlap-free ii for all x in X , h(x) is overlap-free. As a consequence, we observe the particular case X = fbbabaag which improves the previous characterization of Berstel-S e ebold 2]. R esum e Nous donnons une caract erisation de tous les ensembles X tels qu'un morphisme h sur fa; bg est sans chevauchement si ...
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We prove that a morphism h over a two-letter alphabet {a, b} is overlap-free, i.e., maps overlap-free words into overlap-free words, iff the word h(abbabaab) is overlap-free. As a consequence, we obtain a simple proof of the fact that the only infinite overlap-free words that can be obtained by iterating a morphism are the Thue-Morse sequence and its opposite. RLsumP Nous prouvons qu’un morphis...
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A method to represent certain words on a binary alphabet by shorter words on a larger alphabet is introduced. We prove that overlap-free words are represented by the words of a rational language. Several consequences are derived concerning the density function of the set of overlap-free words on a binary alphabet and the prolongability of overlap-free words. In particular, efficient algorithms ...
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ژورنال
عنوان ژورنال: Discrete Applied Mathematics
سال: 2004
ISSN: 0166-218X
DOI: 10.1016/j.dam.2003.10.005