Results 31 to 40 of about 421 (111)
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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Wilf classification of triples of 4-letter patterns I [PDF]
Discrete Mathematics & Theoretical Computer Science, 2017 This paper is first part of a complete paper in arXiv , see 1605.04969.
David Callan +2 more
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Equivalences for pattern avoiding involutions and classification [PDF]
Discrete Mathematics & Theoretical Computer Science, 2008 We complete the Wilf classification of signed patterns of length 5 for both signed permutations and signed involutions. New general equivalences of patterns are given which prove Jaggard's conjectures concerning involutions in the symmetric group ...
Mark Dukes +3 more
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Inversion Polynomials for Permutations Avoiding Consecutive Patterns [PDF]
, 2014 In 2012, Sagan and Savage introduced the notion of $st$-Wilf equivalence for a statistic $st$ and for sets of permutations that avoid particular permutation patterns which can be extended to generalized permutation patterns.
Cameron, Naiomi, Killpatrick, Kendra
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Wilf-equivalence for singleton classes
Advances in Applied Mathematics, 2007 Given \(n\) and a permutation matrix \(M\) of rank less than \(n\), how many \(n \times n\) permutation matrices do \textit{not} have \(M\) as a submatrix? Letting \(S_n(M)\) be the set of \(n \times n\) permutation matrices not admitting \(M\) as a submatrix, we want \(| S_n(M)| \).
Backelin, Jörgen +2 more
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Rook and Wilf equivalence of integer partitions [PDF]
European Journal of Combinatorics, 2018 27, European Journal of Combinatorics ...
Jonathan Bloom, Dan Saracino
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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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Wilf-Equivalence on $k$-ary Words, Compositions, and Parking Functions [PDF]
The Electronic Journal of Combinatorics, 2009 In this paper, we study pattern-avoidance in the set of words over the alphabet $[k]$. We say that a word $w\in[k]^n$ contains a pattern $\tau\in[\ell]^m$, if $w$ contains a subsequence order-isomorphic to $\tau$. This notion generalizes pattern-avoidance in permutations.
Jelínek, Vít, Mansour, Toufik
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On Super-Strong Wilf Equivalence Classes of Permutations
The Electronic Journal of Combinatorics, 2018 Super-strong Wilf equivalence is a type of Wilf equivalence on words that was originally introduced as strong Wilf equivalence by Kitaev et al. [Electron. J. Combin. 16(2)] in $2009$. We provide a necessary and sufficient condition for two permutations in $n$ letters to be super-strongly Wilf equivalent, using distances between letters within a ...
Hadjiloucas, Demetris +2 more
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Generating Permutations with Restricted Containers [PDF]
, 2018 We investigate a generalization of stacks that we call $\mathcal{C}$-machines. We show how this viewpoint rapidly leads to functional equations for the classes of permutations that $\mathcal{C}$-machines generate, and how these systems of functional ...
Albert, Michael H. +4 more
core +3 more sources