On θ-Episturmian Words
نویسندگان
چکیده
In this paper we study a class of infinite words on a finite alphabet A whose factors are closed under the image of an involutory antimorphism θ of the free monoid A∗. We show that given a recurrent infinite word ω ∈ AN, if there exists a positive integer K such that for each n ≥ 1 the word ω has 1) cardA + (n − 1)K distinct factors of length n, and 2) a unique right and a unique left special factor of length n, then there exists an involutory antimorphism θ of the free monoid A∗ preserving the set of factors of ω.
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