Enumeration Schemes for Permutations Avoiding Barred Patterns
نویسنده
چکیده
We give the first comprehensive collection of enumeration results for permutations that avoid barred patterns of length 6 4. We then use the method of prefix enumeration schemes to find recurrences counting permutations that avoid a barred pattern of length > 4 or a set of barred patterns.
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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ورودعنوان ژورنال:
- Electr. J. Comb.
دوره 17 شماره
صفحات -
تاریخ انتشار 2010