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On the number of Abelian square-free words on four letters

✍ Scribed by Arturo Carpi

Publisher
Elsevier Science
Year
1998
Tongue
English
Weight
786 KB
Volume
81
Category
Article
ISSN
0166-218X

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✦ Synopsis

An Abelian square-free substitution on four letters is exhibited.

We derive that. on a fourletter alphabet, the number of Abelian square-free words of each length grows exponentially. infinite Abelian square-free words are uncountable and the monoid of Abelian square-free endomorphisms is not finitely generated.

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