Enumeration Schemes for Words Avoiding Permutations
نویسنده
چکیده
The enumeration of permutation classes has been accomplished with a variety of techniques. One wide-reaching method is that of enumeration schemes, introduced by Zeilberger and extended by Vatter. In this paper we further extend the method of enumeration schemes to words avoiding permutation patterns. The process of finding enumeration schemes is programmable and allows for the automatic enumeration of many classes of pattern-avoiding words.
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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