Results 31 to 40 of about 176,018 (136)
Pattern avoidance for set partitions \`a la Klazar [PDF]
Discrete Mathematics & Theoretical Computer Science, 2016 In 2000 Klazar introduced a new notion of pattern avoidance in the context of set partitions of $[n]=\{1,\ldots, n\}$. The purpose of the present paper is to undertake a study of the concept of Wilf-equivalence based on Klazar's notion.
Jonathan Bloom, Dan Saracino
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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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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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Two examples of unbalanced Wilf-equivalence [PDF]
Journal of Combinatorics, 2015 10 pages, minor revision, to appear in Journal of ...
Burstein, Alexander, Pantone, Jay
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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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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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A General Theory of Wilf-Equivalence for Catalan Structures [PDF]
The Electronic Journal of Combinatorics, 2015 The existence of apparently coincidental equalities (also called Wilf-equivalences) between the enumeration sequences or generating functions of various hereditary classes of combinatorial structures has attracted significant interest. We investigate such coincidences among non-crossing matchings and a variety of other Catalan structures including Dyck
Albert Michael, Bouvel Mathilde
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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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Wilf classification of triples of 4-letter patterns II [PDF]
Discrete Mathematics & Theoretical Computer Science, 2017 this is the second part of a complete paper in arXiv, see 1605 ...
David Callan +2 more
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