Results 31 to 40 of about 208 (162)
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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On hyperbolic k-Pell quaternions sequences [PDF]
, 2018 In this paper we introduce the hyperbolic k-Pell functions and new classes of quaternions associated with this type of functions are presented.
Catarino, Paula
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On the asymptotics of the rescaled Appell polynomials [PDF]
, 2020 18 pags., 6 figs. -- MSC:41A60 30E15 05A15 11C08We introduce a new representation for the rescaled Appell polynomials and use it to obtain asymptotic expansions to arbitrary order.
Sánchez Villaseñor, Eduardo Jesús +5 more
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The log-concavity of the q-derangement numbers of type B
Open Mathematics, 2018 Recently, Chen and Xia proved that for n ≥ 6, the q-derangement numbers Dn(q) are log-concave except for the last term when n is even. In this paper, employing a recurrence relation for DnB(q) $\begin{array}{} \displaystyle D^B_n(q) \end{array ...
Liu Eric H., Du Wenjing
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Forum of Mathematics, Sigma, 2023 Remixed Eulerian numbers are a polynomial q-deformation of Postnikov’s mixed Eulerian numbers. They arose naturally in previous work by the authors concerning the permutahedral variety and subsume well-known families of polynomials such as q-binomial ...
Philippe Nadeau, Vasu Tewari
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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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Negative moments of orthogonal polynomials
Forum of Mathematics, Sigma, 2023 If a sequence indexed by nonnegative integers satisfies a linear recurrence without constant terms, one can extend the indices of the sequence to negative integers using the recurrence.
Jihyeug Jang +4 more
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A note on Eulerian numbers and Toeplitz matrices
Special Matrices, 2020 This note presents a new formula of Eulerian numbers derived from Toeplitz matrices via Riordan array approach.
He Tian-Xiao, Shiue Peter J.-S.
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Refined ratio monotonicity of the coordinator polynomials of the root lattice of type Bn
Open Mathematics, 2023 Ratio monotonicity, a property stronger than both log-concavity and the spiral property, describes the behavior of the coefficients of many classical polynomials.
Su Xun-Tuan, Sun Fan-Bo
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