Pattern avoidance in compositions and multiset permutations
نویسندگان
چکیده
منابع مشابه
Pattern avoidance in compositions and multiset permutations
One of the most arresting phenomena in the theory of pattern avoidance by permutations is the fact that the number of permutations of n letters that avoid a pattern π of 3 letters is independent of π. In this note we exhibit two generalizations of this fact, to ordered partitions, a.k.a. compositions, of an integer, and to permutations of multisets. It is remarkable that the conclusions are in ...
متن کاملPattern Avoidance in Multiset Permutations: Bijective Proof
A permutation σ = σ1σ2 . . . σn of n letters contains the pattern τ = τ1τ2 . . . τk of k letters if for some i1 < i2 < · · · < ik we have σis < σit whenever τs < τt. A permutation is said to avoid any pattern it does not contain. It is well-known that the number of permutations of n letters that avoid a pattern τ of 3 letters is independent of τ . Savage and Wilf [3] have shown the same result ...
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ژورنال
عنوان ژورنال: Advances in Applied Mathematics
سال: 2006
ISSN: 0196-8858
DOI: 10.1016/j.aam.2005.06.003