منابع مشابه
Small Permutation Classes
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This article presents a methodology that automatically derives a combinatorial specification for the permutation class C = Av(B), given its basis B of excluded patterns and the set of simple permutations in C, when these sets are both finite. This is achieved considering both pattern avoidance and pattern containment constraints in permutations. The obtained specification yields a system of equ...
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Each length k pattern occurs equally often in the set Sn of all permutations of length n, but the same is not true in general for a proper subset of Sn. Miklós Bóna recently proved that if we consider the set of n-permutations avoiding the pattern 132, all other non-monotone patterns of length 3 are equally common. In this paper we focus on the set Avn(123) of n-permutations avoiding 123, and g...
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ژورنال
عنوان ژورنال: Proceedings of the London Mathematical Society
سال: 2011
ISSN: 0024-6115
DOI: 10.1112/plms/pdr017