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Related papers: Bruhat graphs and pattern avoidance

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Graph Drawing Beyond Planarity is a rapidly growing research area that classifies and studies geometric representations of non-planar graphs in terms of forbidden crossing configurations. Aim of this survey is to describe the main research…

Computational Geometry · Computer Science 2019-09-04 Walter Didimo , Giuseppe Liotta , Fabrizio Montecchiani

We study groups generated by sets of pattern avoiding permutations. In the first part of the paper we prove some general results concerning the structure of such groups. In the second part we carry out a case-by-case analysis of groups…

Combinatorics · Mathematics 2024-07-08 Marilena Barnabei , Niccolò Castronuovo , Matteo Silimbani

If a graph can be drawn on the torus so that every two independent edges cross an even number of times, then the graph can be embedded on the torus.

Discrete Mathematics · Computer Science 2021-04-14 Radoslav Fulek , Michael J. Pelsmajer , Marcus Schaefer

Knots are commonly represented and manipulated via diagrams, which are decorated planar graphs. When such a knot diagram has low treewidth, parameterized graph algorithms can be leveraged to ensure the fast computation of many invariants…

Computational Geometry · Computer Science 2023-03-16 Corentin Lunel , Arnaud de Mesmay

There is a deep connection between permutations and trees. Certain sub-structures of permutations, called sub-permutations, bijectively map to sub-trees of binary increasing trees. This opens a powerful tool set to study enumerative and…

Combinatorics · Mathematics 2014-07-02 Filippo Disanto , Thomas Wiehe

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

A permutation graph is a graph that can be derived from a permutation, where the vertices correspond to letters of the permutation, and the edges represent inversions. We provide a construction to show that there are infinitely many…

Combinatorics · Mathematics 2019-10-23 Aysel Erey , Zachary Gershkoff , Amanda Lohss , Ranjan Rohatgi

We enumerate permutations that avoid all but one of the $k$ patterns of length $k$ starting with a monotone increasing subsequence of length $k-1$. We compare the size of such permutation classes to the size of the class of permutations…

Combinatorics · Mathematics 2022-08-23 Miklós Bóna , Jay Pantone

Computing a morph between two drawings of a graph is a classical problem in computational geometry and graph drawing. While this problem has been widely studied in the context of planar graphs, very little is known about the existence of…

Computational Geometry · Computer Science 2021-05-28 Patrizio Angelini , Michael A. Bekos , Fabrizio Montecchiani , Maximilian Pfister

Multidimensional permutations, or $d$-permutations, are represented by their diagrams on $[n]^d$ such that there exists exactly one point per hyperplane $x_i$ that satisfies $x_i= j$ for $i \in [d]$ and $j \in [n]$. Bonichon and Morel…

Combinatorics · Mathematics 2024-04-25 Nathan Sun

Pattern avoidance classes of permutations that cannot be expressed as unions of proper subclasses can be described as the set of subpermutations of a single bijection. In the case that this bijection is a permutation of the natural numbers…

Combinatorics · Mathematics 2007-05-23 M. D. Atkinson , M. M. Murphy , N. Ruskuc

Rothe diagrams are diagrams which track inversions of a permutation. We define six main properties that Rothe diagrams fulfill: the southwest, dot, popping, numbering, step-out avoiding, and empty cell gap rules. We prove that -- given an…

Combinatorics · Mathematics 2023-03-22 Ben Gillen , Jonathan Michala

For each permutation $w$, we can construct a collection of hyperplanes $\mathcal{A}_w$ according to the inversions of $w$, which is called the inversion hyperplane arrangement associated to $w$. It was conjectured by Postnikov and confirmed…

Combinatorics · Mathematics 2020-06-16 Neil J. Y. Fan

In this paper we study pattern avoidance for affine permutations. In particular, we show that for a given pattern p, there are only finitely many affine permutations in $\widetilde{S}_n$ that avoid p if and only if p avoids the pattern 321.…

Combinatorics · Mathematics 2010-11-15 Andrew Crites

We investigate the problem of drawing graphs in 2D and 3D such that their edges (or only their vertices) can be covered by few lines or planes. We insist on straight-line edges and crossing-free drawings. This problem has many connections…

Computational Geometry · Computer Science 2016-09-02 Steven Chaplick , Krzysztof Fleszar , Fabian Lipp , Alexander Ravsky , Oleg Verbitsky , Alexander Wolff

Egge and Mansour have recently studied permutations which avoid 1243 and 2143 regarding the occurrence of certain additional patterns. Some of the open questions related to their work can easily be answered by using permutation diagrams.…

Combinatorics · Mathematics 2007-05-23 Astrid Reifegerste

We determine which properties of 2-layer drawings characterise bipartite graphs of bounded pathwidth.

Combinatorics · Mathematics 2022-07-15 David R. Wood

The poset of permutations of [n] under Bruhat ordering is studied. We give nontrivial upper and lower bounds for the number of comparable pairs of permutations in both the weak and strong versions of this order. In light of numerical…

Probability · Mathematics 2007-05-23 Adam Hammett , Boris Pittel

Graph drawing beyond planarity focuses on drawings of high visual quality for non-planar graphs which are characterized by certain forbidden edge configurations. A natural criterion for the quality of a drawing is the number of edge…

Computational Geometry · Computer Science 2021-05-27 Nathan van Beusekom , Irene Parada , Bettina Speckmann

In this paper, we find explicit formulas or generating functions for the cardinalities of the sets $S_n(T,\tau)$ of all permutations in $S_n$ that avoid a pattern $\tau\in S_k$ and a set $T$, $|T|\geq 2$, of patterns from $S_3$. The main…

Combinatorics · Mathematics 2007-05-23 T. Mansour