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Related papers: Pattern avoidance with involution

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We present a family of avoidable formulas with reversal whose avoidability index is unbounded. We also complete the determination of the avoidability index of the formulas with reversal in the 3-avoidance basis.

Combinatorics · Mathematics 2021-03-16 Pascal Ochem

We give convolution identities without binomial coefficients for Tetranacci numbers and convolution identities with binomial coefficients for Tetranacci and Tetranacci-type numbers.

Number Theory · Mathematics 2016-09-20 Rusen Li

The study of pattern containment and avoidance for linear permutations is a well-established area of enumerative combinatorics. A cyclic permutation is the set of all rotations of a linear permutation. Callan initiated the study of…

Classical pattern avoidance and occurrence are well studied in the symmetric group $\mathcal{S}_{n}$. In this paper, we provide explicit recurrence relations to the generating functions counting the number of classical pattern occurrence in…

Combinatorics · Mathematics 2023-06-22 Dun Qiu , Jeffrey Remmel

There are several versions of permutation pattern avoidance that have arisen in the literature, and some known examples of two different types of pattern avoidance coinciding. In this paper, we examine barred patterns and vincular patterns.…

Combinatorics · Mathematics 2013-01-28 Bridget Eileen Tenner

This thesis deals with three different aspects of the combinatorics of permutations. In the first two papers, two flavours of pattern avoiding permutations are examined; and in the third paper Young tableaux, which are closely related to…

Combinatorics · Mathematics 2009-08-04 Erik Ouchterlony

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…

Combinatorics · Mathematics 2008-01-22 Mark Dukes , Vit Jelínek , Toufik Mansour , Astrid Reifegerste

We construct an intriguing bijection between $021$-avoiding inversion sequences and $(2413,4213)$-avoiding permutations, which proves a sextuple equidistribution involving double Eulerian statistics. Two interesting applications of this…

Combinatorics · Mathematics 2016-12-20 Zhicong Lin , Dongsu Kim

Permutations avoiding all patterns of a given shape (in the sense of Robinson-Schensted-Knuth) are considered. We show that the shapes of all such permutations are contained in a suitable thick hook, and deduce an exponential growth rate…

Combinatorics · Mathematics 2007-05-23 Ron M. Adin , Yuval Roichman

Shuffle algebras are monoids for an unconvential monoidal category structure on graded vector spaces. We present two homological results on shuffle algebras with monomial relations, and use them to prove exact and asymptotic results on…

Combinatorics · Mathematics 2017-02-16 Vladimir Dotsenko , Anton Khoroshkin

We explore how the asymptotic structure of a random permutation of $[n]$ with $m$ inversions evolves, as $m$ increases, establishing thresholds for the appearance and disappearance of any classical, consecutive or vincular pattern. The…

Combinatorics · Mathematics 2024-08-13 David Bevan , Dan Threlfall

In this paper, we study pattern avoidance for stabilized-interval-free (SIF) permutations. These permutations are contained in the set of indecomposable permutations and in the set of derangements. We enumerate pattern-avoiding SIF…

Combinatorics · Mathematics 2025-01-13 Daniel Birmajer , Juan B. Gil , Jordan O. Tirrell , Michael D. Weiner

We prove a generalization of a conjecture of Dokos, Dwyer, Johnson, Sagan, and Selsor giving a recursion for the inversion polynomial of 321-avoiding permutations. We also answer a question they posed about finding a recursive formulas for…

Combinatorics · Mathematics 2012-11-21 Szu-En Cheng , Sergi Elizalde , Anisse Kasraoui , Bruce Sagan

We associate to every central simple algebra with involution of orthogonal type in characteristic two a totally singular quadratic form which reflects certain anisotropy properties of the involution. It is shown that this quadratic form can…

Rings and Algebras · Mathematics 2017-01-10 A. -H. Nokhodkar

Circular permutations on {1,2,...,n} that avoid a given pattern correspond to ordinary (linear) permutations that end with n and avoid all cyclic rotations of the pattern. Three letter patterns are all but unavoidable in circular…

Combinatorics · Mathematics 2007-05-23 David Callan

Using techniques from Poisson approximation, we prove explicit error bounds on the number of permutations that avoid any pattern. Most generally, we bound the total variation distance between the joint distribution of pattern occurrences…

Combinatorics · Mathematics 2023-06-22 Harry Crane , Stephen DeSalvo

In the interest of studying formulas with reversal of high avoidability index, we find $n$-avoidance bases for formulas with reversal for $n\in\{1,2,3\}$. We demonstrate that there is a unique formula with reversal in each of these three…

Combinatorics · Mathematics 2018-04-13 James Currie , Lucas Mol , Narad Rampersad

We characterize permutations whose Bruhat graphs can be drawn in the plane and those whose Bruhat graphs can be drawn in the torus. In particular, we show these properties are characterized by avoiding finitely many permutations.

Combinatorics · Mathematics 2017-01-13 Christopher Conklin , Alexander Woo

We investigate pattern avoidance in alternating permutations and generalizations thereof. First, we study pattern avoidance in an alternating analogue of Young diagrams. In particular, we extend Babson-West's notion of shape-Wilf…

Combinatorics · Mathematics 2014-10-21 Nihal Gowravaram , Ravi Jagadeesan

We give an explicit formula for the number of permutations avoiding cyclically a consecutive pattern in terms of the spectrum of the associated operator of the consecutive pattern. As an example, the number of cyclically consecutive…

Combinatorics · Mathematics 2013-12-10 Richard Ehrenborg