On the Number of Indecomposable Permutations with a Given Number of Cycles
نویسندگان
چکیده
منابع مشابه
Indecomposable permutations with a given number of cycles
A permutation a1a2 . . . an is indecomposable if there does not exist p < n such that a1a2 . . . ap is a permutation of {1, 2, . . . , p}. We compute the asymptotic probability that a permutation of Sn with m cycles is indecomposable as n goes to infinity with m/n fixed. The error term is O( log(n−m) n−m ). The asymptotic probability is monotone in m/n, and there is no threshold phenomenon: it ...
متن کاملOn the Number of Indecomposable Permutations with a Given Number of Cycles
Abstract. A permutation a1a2 . . . an is indecomposable if there does not exist p < n such that a1a2 . . . ap is a permutation of {1, 2, . . . , p}. We consider the probability that a permutation of Sn with m cycles is indecomposable and prove that this probability is monotone non-increasing in n. We compute also the asymptotic probability when n goes to infinity with m/n tending to a fixed rat...
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Let σ ∈ Sk and τ ∈ Sn be permutations. We say τ contains σ if there exist 1 ≤ x1 < x2 < . . . < xk ≤ n such that τ(xi) < τ(xj) if and only if σ(i) < σ(j). If τ does not contain σ we say τ avoids σ. Let F (n, σ) = |{τ ∈ Sn| τ avoids σ}|. Stanley and Wilf conjectured that for any σ ∈ Sk there exists a constant c = c(σ) such that F (n, σ) ≤ cn for all n. Here we prove the following weaker statemen...
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ژورنال
عنوان ژورنال: The Electronic Journal of Combinatorics
سال: 2012
ISSN: 1077-8926
DOI: 10.37236/2071