Results 21 to 30 of about 421 (111)

A New Class of Wilf-Equivalent Permutations [PDF]

Journal of Algebraic Combinatorics, 2002
20 pages, 14 figures, corrected ...
Stankova, Zvezdelina, West, Julian
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Refined Wilf-equivalences by Comtet statistics

Electronic Research Archive, 2021
<p style='text-indent:20px;'>We launch a systematic study of the refined Wilf-equivalences by the statistics <inline-formula><tex-math id="M1">$ {\mathsf{comp}} $</tex-math></inline-formula> and <inline-formula><tex-math id="M2">$ {\mathsf{iar}} $</tex-math></inline-formula>, where <inline ...
Fu, Shishuo, Lin, Zhicong, Wang, Yaling
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On avoidance of patterns of the form σ-τ by words over a finite alphabet [PDF]

Discrete Mathematics & Theoretical Computer Science, 2015
Vincular or dashed patterns resemble classical patterns except that some of the letters within an occurrence are required to be adjacent. We prove several infinite families of Wilf-equivalences for $k$-ary words involving vincular patterns containing a ...
Toufik Mansour, Mark Shattuck
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Wilf equivalences between vincular patterns in inversion sequences [PDF]

Applied Mathematics and Computation, 2021
18 pages, 9 ...
Auli, Juan S., Elizalde, Sergi
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Wilf equivalence relations for consecutive patterns [PDF]

Advances in Applied Mathematics, 2018
Two permutations $π$ and $τ$ are c-Wilf equivalent if, for each $n$, the number of permutations in $S_n$ avoiding $π$ as a consecutive pattern (i.e., in adjacent positions) is the same as the number of those avoiding $τ$. In addition, $π$ and $τ$ are strongly c-Wilf equivalent if, for each $n$ and $k$, the number of permutations in $S_n$ containing $k$
Tim Dwyer, Sergi Elizalde
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Patterns in matchings and rook placements [PDF]

Discrete Mathematics & Theoretical Computer Science, 2013
Extending the notion of pattern avoidance in permutations, we study matchings and set partitions whose arc diagram representation avoids a given configuration of three arcs.
Jonathan Bloom, Sergi Elizalde
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Pattern-Avoidance in Binary Fillings of Grid Shapes (short version) [PDF]

Discrete Mathematics & Theoretical Computer Science, 2008
A $\textit{grid shape}$ is a set of boxes chosen from a square grid; any Young diagram is an example. This paper considers a notion of pattern-avoidance for $0-1$ fillings of grid shapes, which generalizes permutation pattern-avoidance.
Alexey Spiridonov
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Modified Growth Diagrams, Permutation Pivots, and the BWX Map $\phi^*$ [PDF]

Discrete Mathematics & Theoretical Computer Science, 2012
In their paper on Wilf-equivalence for singleton classes, Backelin, West, and Xin introduced a transformation $\phi^*$, defined by an iterative process and operating on (all) full rook placements on Ferrers boards. Bousquet-Mélou and Steingrimsson proved
Jonathan Bloom, Dan Saracino
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On Wilf Equivalence for Alternating Permutations [PDF]

The Electronic Journal of Combinatorics, 2013
In this paper, we obtain several new classes of Wilf-equivalent patterns for alternating permutations. In particular, we prove that for any nonempty pattern $\tau$, the patterns $12\ldots k\oplus\tau$ and $k\ldots 21\oplus\tau$ are Wilf-equivalent for  alternating permutations, paralleling a result of Backelin, West, and Xin for Wilf equivalence for ...
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Some Wilf-equivalences for vincular patterns [PDF]

Journal of Combinatorics, 2015
20 pages. To appear in the Journal of Combinatorics, Special Issue for the Proceedings of Permutation Patterns ...
Baxter, Andrew M., Shattuck, Mark
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