Results 21 to 30 of about 122,748 (264)
Deodhar Elements in Kazhdan-Lusztig Theory [PDF]
Discrete Mathematics & Theoretical Computer Science, 2008 The Kazhdan-Lusztig polynomials for finite Weyl groups arise in representation theory as well as the geometry of Schubert varieties. It was proved very soon after their introduction that they have nonnegative integer coefficients, but no simple all ...
Brant Jones
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Discrete Mathematics & Theoretical Computer Science, 2014 A general lattice theoretic construction of Reading constructs Hopf subalgebras of the Malvenuto-Reutenauer Hopf algebra (MR) of permutations. The products and coproducts of these Hopf subalgebras are defined extrinsically in terms of the embedding in MR.
Shirley Law
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Crucial abelian k-power-free words [PDF]
Discrete Mathematics & Theoretical Computer Science, 2010 Combinatorics
Amy Glen +2 more
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Advances in Applied Mathematics, 2012 We extend the notion of consecutive pattern avoidance to considering sums over all permutations where each term is a product of weights depending on each consecutive pattern of a fixed length. We study the problem of finding the asymptotics of these sums. Our technique is to extend the spectral method of Ehrenborg, Kitaev and Perry.
Richard Ehrenborg, JiYoon Jung
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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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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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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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Pattern Avoidance in Reverse Double Lists [PDF]
Discrete Mathematics & Theoretical Computer Science, 2018 In this paper, we consider pattern avoidance in a subset of words on $\{1,1,2,2,\dots,n,n\}$ called reverse double lists. In particular a reverse double list is a word formed by concatenating a permutation with its reversal.
Monica Anderson +3 more
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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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