Results 21 to 30 of about 143 (87)
Enumerating two permutation classes by the number of cycles [PDF]
Discrete Mathematics & Theoretical Computer Science, 2022 We enumerate permutations in the two permutation classes $\text{Av}_n(312, 4321)$ and $\text{Av}_n(321, 4123)$ by the number of cycles each permutation admits. We also refine this enumeration with respect to several statistics.
Kassie Archer
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Enumeration of Stack-Sorting Preimages via a Decomposition Lemma [PDF]
Discrete Mathematics & Theoretical Computer Science, 2021 We give three applications of a recently-proven "Decomposition Lemma," which allows one to count preimages of certain sets of permutations under West's stack-sorting map $s$.
Colin Defant
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Sensitivities and block sensitivities of elementary symmetric Boolean functions
Journal of Mathematical Cryptology, 2021 Boolean functions have important applications in molecular regulatory networks, engineering, cryptography, information technology, and computer science. Symmetric Boolean functions have received a lot of attention in several decades.
Zhang Jing, Li Yuan, Adeyeye John O.
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Enumeration of Dumont permutations avoiding certain four-letter patterns [PDF]
Discrete Mathematics & Theoretical Computer Science, 2021 In this paper, we enumerate Dumont permutations of the fourth kind avoiding or containing certain permutations of length 4. We also conjecture a Wilf-equivalence of two 4-letter patterns on Dumont permutations of the first kind.
Alexander Burstein, Opel Jones
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The number of distinct adjacent pairs in geometrically distributed words [PDF]
Discrete Mathematics & Theoretical Computer Science, 2021 A sequence of geometric random variables of length $n$ is a sequence of $n$ independent and identically distributed geometric random variables ($\Gamma_1, \Gamma_2, \dots, \Gamma_n$) where $\mathbb{P}(\Gamma_j=i)=pq^{i-1}$ for $1~\leq~j~\leq~n$ with $p+q=
Margaret Archibald +5 more
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A Symmetric Function of Increasing Forests
Forum of Mathematics, Sigma, 2021 For an indifference graph G, we define a symmetric function of increasing spanning forests of G. We prove that this symmetric function satisfies certain linear relations, which are also satisfied by the chromatic quasisymmetric function and unicellular $\
Alex Abreu, Antonio Nigro
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Enumerating graph embeddings and partial-duals by genus and Euler genus
Enumerative Combinatorics and Applications, 2020 We present an overview of an enumerative approach to topological graph theory, involving the derivation of generating functions for a set of graph embeddings, according to the topological types of their respective surfaces.
J. Gross, T. Tucker
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On Iteration of Bijective Functions with Discontinuities
Annales Mathematicae Silesianae, 2020 We present three different types of bijective functions f : I → I on a compact interval I with finitely many discontinuities where certain iterates of these functions will be continuous.
Fripertinger Harald
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Increasing and Decreasing Subsequences
, 2006 We survey the theory of increasing and decreasing subsequences of permutations. Enumeration problems in this area are closely related to the RSK algorithm.
R. Stanley
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On an alternative sequence comparison statistic of Steele [PDF]
Discrete Mathematics & Theoretical Computer Science, 2020 The purpose of this paper is to study a statistic that is used to compare the similarity between two strings, which is first introduced by Michael Steele in 1982.
Ümit Işlak, Alperen Y. Özdemir
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