Results 1 to 10 of about 2,046 (100)
Inversion sequences avoiding 021 and another pattern of length four [PDF]
Discrete Mathematics & Theoretical Computer Science, 2023 We study the enumeration of inversion sequences that avoid the pattern 021 and another pattern of length four. We determine the generating trees for all possible pattern pairs and compute the corresponding generating functions.
Toufik Mansour, Gökhan Yıldırım
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The number of {1243, 2134}-avoiding permutations [PDF]
Discrete Mathematics & Theoretical Computer Science, 2023 We show that the counting sequence for permutations avoiding both of the (classical) patterns 1243 and 2134 has the algebraic generating function supplied by Vaclav Kotesovec for sequence A164651 in The On-Line Encyclopedia of Integer Sequences.
David Callan
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Permutations avoiding 4321 and 3241 have an algebraic generating function [PDF]
Discrete Mathematics & Theoretical Computer Science, 2022 We show that permutations avoiding both of the (classical) patterns 4321 and 3241 have the algebraic generating function conjectured by Vladimir Kruchinin.
David Callan
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Duality for convolution on subclasses of analytic functions and weighted integral operators
Demonstratio Mathematica, 2023 In this article, we investigate a class of analytic functions defined on the unit open disc U={z:∣z∣0\alpha \gt 0, 0≤β≤10\le \beta \le 1 ...
Amini Ebrahim +3 more
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The dual of number sequences, Riordan polynomials, and Sheffer polynomials
Special Matrices, 2021 In this paper we introduce different families of numerical and polynomial sequences by using Riordan pseudo involutions and Sheffer polynomial sequences.
He Tian-Xiao, Ramírez José L.
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Deepest Nodes in Marked Ordered Trees
Annales Mathematicae Silesianae, 2022 A variation of ordered trees, where each rightmost edge might be marked or not, if it does not lead to an endnode, is investigated. These marked ordered trees were introduced by E. Deutsch et al. to model skew Dyck paths.
Prodinger Helmut
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Generating functions for a lattice path model introduced by Deutsch
Special Matrices, 2021 The lattice path model suggested by E. Deutsch is derived from ordinary Dyck paths, but with additional down-steps of size −3, −5, −7, . . . . For such paths, we find the generating functions of them, according to length, ending at level i, both, when ...
Prodinger Helmut
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Two examples of Wilf-collapse [PDF]
Discrete Mathematics & Theoretical Computer Science, 2021 Two permutation classes, the X-class and subpermutations of the increasing oscillation are shown to exhibit an exponential Wilf-collapse. This means that the number of distinct enumerations of principal subclasses of each of these classes grows much more
Michael Albert +2 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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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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