Results 11 to 20 of about 152 (126)
Further enumeration results concerning a recent equivalence of restricted inversion sequences [PDF]
Discrete Mathematics & Theoretical Computer Science, 2022 Let asc and desc denote respectively the statistics recording the number of ascents or descents in a sequence having non-negative integer entries.
Toufik Mansour, Mark Shattuck
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Positional Marked Patterns in Permutations [PDF]
Discrete Mathematics & Theoretical Computer Science, 2022 We define and study positional marked patterns, permutations $\tau$ where one of elements in $\tau$ is underlined. Given a permutation $\sigma$, we say that $\sigma$ has a $\tau$-match at position $i$ if $\tau$ occurs in $\sigma$ in such a way that ...
Sittipong Thamrongpairoj +1 more
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Antipowers in Uniform Morphic Words and the Fibonacci Word [PDF]
Discrete Mathematics & Theoretical Computer Science, 2021 Fici, Restivo, Silva, and Zamboni define a $k$-antipower to be a word composed of $k$ pairwise distinct, concatenated words of equal length. Berger and Defant conjecture that for any sufficiently well-behaved aperiodic morphic word $w$, there exists a ...
Swapnil Garg
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No extremal square-free words over large alphabets [PDF]
, 2022 A word is square-free if it does not contain any square (a word of the form \(XX\)), and is extremal square-free if it cannot be extended to a new square-free word by inserting a single letter at any position.
Zhang, Shengtong, Hong, Letong
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A bijective proof of Kohnert's rule for Schubert polynomials [PDF]
, 2022 Kohnert proposed a formula for Schubert polynomials as the generating polynomial for certain unit cell diagrams obtained from the diagram of a permutation.
Assaf, Sami H.
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A Bijection on Classes Enumerated by the Schröder Numbers [PDF]
Discrete Mathematics & Theoretical Computer Science, 2017 We consider a sorting machine consisting of two stacks in series where the first stack has the added restriction that entries in the stack must be in decreasing order from top to bottom.
Michael W. Schroeder, Rebecca Smith
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Odd diagrams, Bruhat order, and pattern avoidance [PDF]
, 2022 The odd diagram of a permutation is a subset of the classical diagram with additional parity conditions. In this paper, we study classes of permutations with the same odd diagram, which we call odd diagram classes.
Brenti, Francesco +2 more
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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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The Hurwitz action in complex reflection groups [PDF]
, 2022 We enumerate Hurwitz orbits of shortest reflection factorizations of an arbitrary element in the infinite family \(G(m, p, n)\) of complex reflection groups.
Lewis, Joel Brewster, Wang, Jiayuan
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Chain enumeration, partition lattices and polynomials with only real roots [PDF]
, 2023 The coefficients of the chain polynomial of a finite poset enumerate chains in the poset by their number of elements. The chain polynomials of the partition lattices and their standard type \(B\) analogues are shown to have only real roots.
Kalampogia-Evangelinou, Katerina +1 more
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