Tower-type bounds for unavoidable patterns in words
نویسندگان
چکیده
منابع مشابه
Tower-type bounds for unavoidable patterns in words
A word w is said to contain the pattern P if there is a way to substitute a nonempty word for each letter in P so that the resulting word is a subword of w. Bean, Ehrenfeucht and McNulty and, independently, Zimin characterised the patterns P which are unavoidable, in the sense that any sufficiently long word over a fixed alphabet contains P . Zimin’s characterisation says that a pattern is unav...
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ژورنال
عنوان ژورنال: Transactions of the American Mathematical Society
سال: 2019
ISSN: 0002-9947,1088-6850
DOI: 10.1090/tran/7751