Enumeration Schemes for Words Avoiding Patterns with Repeated Letters
نویسنده
چکیده
In this paper, we discuss the enumeration of words avoiding patterns with repeated letters. More specifically, we find recurrences (i.e. enumeration schemes) counting words avoiding any pattern of length 3 and words avoiding any monotone pattern.
منابع مشابه
Enumeration Schemes for Pattern-avoiding Words and Permutations
OF THE DISSERTATION Enumeration Schemes for Pattern-Avoiding Words and Permutations by Lara Kristin Pudwell Dissertation Director: Doron Zeilberger Let p = p1 · · · pn ∈ Sn and q = q1 · · · qm ∈ Sm. We say that p contains q as a pattern if there are indices 1 ≤ i1 < · · · < im ≤ n such that pij < pik ⇐⇒ qi < qk; otherwise, p avoids q. The study of pattern avoidance in permutations is well studi...
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تاریخ انتشار 2007