Results 41 to 50 of about 549,106 (324)
Matchings Avoiding Partial Patterns [PDF]
The Electronic Journal of Combinatorics, 2006 We show that matchings avoiding a certain partial pattern are counted by the $3$-Catalan numbers. We give a characterization of $12312$-avoiding matchings in terms of restrictions on the corresponding oscillating tableaux. We also find a bijection between matchings avoiding both patterns $12312$ and $121323$ and Schröder paths without peaks at level ...
William Y. C. Chen +2 more
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Pattern avoidance by palindromes
Theoretical Computer Science, 2009 zbMATH Open Web Interface contents unavailable due to conflicting licenses.
I. A. Mikhailova, Mikhail V. Volkov 0001
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Bounded affine permutations I. Pattern avoidance and enumeration [PDF]
Discrete Mathematics & Theoretical Computer Science, 2021 We introduce a new boundedness condition for affine permutations, motivated by the fruitful concept of periodic boundary conditions in statistical physics. We study pattern avoidance in bounded affine permutations.
Neal Madras, Justin M. Troyka
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Doubled Patterns are 3-Avoidable [PDF]
The Electronic Journal of Combinatorics, 2016 In combinatorics on words, a word $w$ over an alphabet $\Sigma$ is said to avoid a pattern $p$ over an alphabet $\Delta$ if there is no factor $f$ of $w$ such that $f=h(p)$ where $h: \Delta^*\to\Sigma^*$ is a non-erasing morphism. A pattern $p$ is said to be $k$-avoidable if there exists an infinite word over a $k$-letter alphabet that avoids $p$.
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European Journal of Combinatorics, 2001 Recently, Babson and Steingrimsson have introduced generalised permutation patterns that allow the requirement that two adjacent letters in a pattern must be adjacent in the permutation. We consider pattern avoidance for such patterns, and give a complete solution for the number of permutations avoiding any single pattern of length three with exactly ...
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Permutation Pattern matching in (213, 231)-avoiding permutations [PDF]
Discrete Mathematics & Theoretical Computer Science, 2017 Given permutations σ of size k and π of size n with k < n, the permutation pattern matching problem is to decide whether σ occurs in π as an order-isomorphic subsequence.
Both Neou +2 more
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Pattern Avoidance by Even Permutations [PDF]
The Electronic Journal of Combinatorics, 2011 We study questions of even-Wilf-equivalence, the analogue of Wilf-equivalence when attention is restricted to pattern avoidance by permutations in the alternating group. Although some Wilf-equivalence results break when considering even-Wilf-equivalence analogues, we prove that other Wilf-equivalence results continue to hold in the even-Wilf ...
Andrew Baxter, Aaron D. Jaggard
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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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Random Structures & AlgorithmsAbstract The theory of limits of permutations leads to limit objects called permutons, which are certain Borel measures on the unit square. We prove that permutons avoiding a given permutation of order have a particularly simple structure.
Frederik Garbe +3 more
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Pattern avoidance of generalized permutations [PDF]
Advances in Applied Mathematics, 2019 In this paper, we study pattern avoidances of generalized permutations and show that the number of all generalized permutations avoiding $π$ is independent of the choice of $π\in S_3$, which extends the classic results on permutations avoiding $π\in S_3$.
Zhousheng Mei, Suijie Wang
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