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Let B be a finite collection of geometric (not necessarily convex) bodies in the plane. Clearly, this class of geometric objects naturally generalizes the class of disks, lines, ellipsoids, and even convex polygons. We consider geometric…

Discrete Mathematics · Computer Science 2013-08-29 Alexander Grigoriev , Athanassios Koutsonas , Dimitrios M. Thilikos

A curve in the plane is $x$-monotone if every vertical line intersects it at most once. A family of curves are called pseudo-segments if every pair of them have at most one point in common. We construct $2^{\Omega(n^{4/3})}$ families, each…

Combinatorics · Mathematics 2026-01-12 Jacob Fox , Janos Pach , Andrew Suk

A bisection of a graph is a bipartition of its vertex set such that the two resulting parts differ in size by at most 1, and its size is the number of edges that connect vertices in the two parts. The perfect matching condition and…

Combinatorics · Mathematics 2024-11-19 Jianfeng Hou , Shufei Wu , Yuanyuan Zhong

A class of graphs G is chi-bounded if the chromatic number of the graphs in G is bounded by some function of their clique number. We show that the class of intersection graphs of simple x-monotone curves in the plane intersecting a vertical…

Combinatorics · Mathematics 2013-08-27 Andrew Suk

This document is an informal bibliography of the papers dealing with distributed approximation algorithms. A classic setting for such algorithms is bounded degree graphs, but there is a whole set of techniques that have been developed for…

Data Structures and Algorithms · Computer Science 2023-11-10 Laurent Feuilloley

Chordal graphs are the graphs in which every cycle of length at least four has a chord. A set $S$ is a vertex separator for vertices $a$ and $b$ if the removal of $S$ of the graph separates $a$ and $b$ into distinct connected components. A…

Discrete Mathematics · Computer Science 2018-03-22 Sérgio H. Nogueira , Vinicius F. dos Santos

A pseudoline is a homeomorphic image of the real line in the plane so that its complement is disconnected. An arrangement of pseudolines is a set of pseudolines in which every two cross exactly once. A drawing of a graph is pseudolinear if…

Combinatorics · Mathematics 2018-04-26 Alan Arroyo , Julien Bensmail , R. Bruce Richter

A universal representation theorem is derived that shows any graph is the intersection graph of one chordal graph, a number of co-bipartite graphs, and one unit interval graph. Central to the the result is the notion of the clique cover…

Combinatorics · Mathematics 2015-04-21 Farhad Shahrokhi

Mixed graphs can be seen as digraphs that have both arcs and edges (or digons, that is, two opposite arcs). In this paper, we consider the case where such graphs are bipartite. As main results, we show that in this context the Moore-like…

Combinatorics · Mathematics 2016-11-08 C. Dalfó , M. A. Fiol , N. López

A graph $G$ has $p$-intersection number at most $d$ if it is possible to assign to every vertex $u$ of $G$, a subset $S(u)$ of some ground set $U$ with $|U|=d$ in such a way that distinct vertices $u$ and $v$ of $G$ are adjacent in $G$ if…

Combinatorics · Mathematics 2015-07-16 Claudson F. Bornstein , Jose W. C. Pinto , Dieter Rautenbach , Jayme L. Szwarcfiter

We consider the flip-width of geometric graphs, a notion of graph width recently introduced by Toru\'nczyk. We prove that many different types of geometric graphs have unbounded flip-width. These include interval graphs, permutation graphs,…

Computational Geometry · Computer Science 2023-06-23 David Eppstein , Rose McCarty

In the study of full bubble model graphs of bounded clique-width and bounded linear clique-width, we determined complete sets of forbidden induced subgraphs, that are minimal in the class of full bubble model graphs. In this note, we show…

Discrete Mathematics · Computer Science 2014-01-29 Daniel Meister , Udi Rotics

We study limits of convergent sequences of string graphs, that is, graphs with an intersection representation consisting of curves in the plane. We use these results to study the limiting behavior of a sequence of random string graphs. We…

Combinatorics · Mathematics 2014-03-13 Svante Janson , Andrew J. Uzzell

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

Motivated by the concept of well-covered graphs, we define a graph to be well-bicovered if every vertex-maximal bipartite subgraph has the same order (which we call the bipartite number). We first give examples of them, compare them with…

Combinatorics · Mathematics 2019-09-18 Wayne Goddard , Kirsti Kuenzel , Eileen Melville

The L-intersection graphs are the graphs that have a representation as intersection graphs of axis parallel shapes in the plane. A subfamily of these graphs are {L, |, --}-contact graphs which are the contact graphs of axis parallel L, |,…

Computational Geometry · Computer Science 2017-07-31 Daniel Gonçalves , Lucas Isenmann , Claire Pennarun

An ordered graph is a graph with a total order over its vertices. A linear layout of an ordered graph is a partition of the edges into sets of either non-crossing edges, called stacks, or non-nesting edges, called queues. The stack (queue)…

Discrete Mathematics · Computer Science 2024-12-18 Deborah Haun , Laura Merker , Sergey Pupyrev

In this dissertation, we explore the structure of inversion graphs of permutations--a class of graphs that naturally arises by representing each permutation as a graph, where vertices correspond to entries and edges encode inversions.…

Combinatorics · Mathematics 2025-06-30 Sean Mandrick

Using a notation of corner between edges when graph has a fixed rotation, i.e. cyclical order of edges around vertices, we define combinatorial objects - combinatorial maps as pairs of permutations, one for vertices and one for faces.…

Combinatorics · Mathematics 2009-09-02 Dainis Zeps

Many "good" topologies for interconnection networks are based on line digraphs of regular digraphs. These digraphs support unitary matrices. We propose the property "being the digraph of a unitary matrix" as additional criterion for the…

Discrete Mathematics · Computer Science 2007-05-23 Simone Severini
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