A powerful abelian square-free substitution over 4 letters
نویسندگان
چکیده
منابع مشابه
New Abelian Square-Free DT0L-Languages over 4 Letters
In 1906 Axel Thue [34] started the systematic study of structures in words. Consequently, he studied basic objects of theoretical computer science long before the invention of the computer or DNA. In 1961 Paul Erdös [13] raised the question whether abelian squares can be avoided in infinitely long words. In 1992, we presented in [19], see also [20–23], an abelian square-free (a-2-free) endomorp...
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ژورنال
عنوان ژورنال: Theoretical Computer Science
سال: 2009
ISSN: 0304-3975
DOI: 10.1016/j.tcs.2009.05.027