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Related papers: Crossing Numbers of Beyond-Planar Graphs

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A graph drawn in the plane is called k-quasi-planar if it does not contain k pairwise crossing edges. It has been conjectured for a long time that for every fixed k, the maximum number of edges of a k-quasi-planar graph with n vertices is…

Combinatorics · Mathematics 2011-12-13 Jacob Fox , Janos Pach , Andrew Suk

A graph $G=(V,E)$ is called 1-planar if it admits a drawing in the plane such that each edge is crossed at most once. In this paper, we study bipartite $1$-planar graphs with prescribed numbers of vertices in partite sets. Bipartite…

Combinatorics · Mathematics 2015-03-05 Július Czap , Jakub Przybyło , Erika Škrabuľáková

Research about crossings is typically about minimization. In this paper, we consider \emph{maximizing} the number of crossings over all possible ways to draw a given graph in the plane. Alpert et al. [Electron. J. Combin., 2009] conjectured…

Computational Geometry · Computer Science 2017-05-16 Markus Chimani , Stefan Felsner , Stephen Kobourov , Torsten Ueckerdt , Pavel Valtr , Alexander Wolff

A graph is 1-planar if it can be drawn on the plane so that each edge is crossed by at most one other edge. In this paper, we confirm the total-coloring conjecture for 1-planar graphs with maximum degree at least 13.

Combinatorics · Mathematics 2013-04-24 Xin Zhang , Jianfeng Hou , Guizhen Liu

In a \emph{fan-planar drawing} of a graph an edge can cross only edges with a common end-vertex. Fan-planar drawings have been recently introduced by Kaufmann and Ueckerdt, who proved that every $n$-vertex fan-planar drawing has at most…

Computational Geometry · Computer Science 2019-09-04 Carla Binucci , Emilio Di Giacomo , Walter Didimo , Fabrizio Montecchiani , Maurizio Patrignani , Ioannis G. Tollis

A graph is 1-planar if it can be drawn on the plane so that each edge is crossed by at most one other edge. In this note we give examples of class two 1-planar graphs with maximum degree six or seven.

Combinatorics · Mathematics 2011-04-26 Xin Zhang

In 1979, Nishizeki and Baybars showed that every planar graph with minimum degree 3 has a matching of size $\frac{n}{3}+c$ (where the constant $c$ depends on the connectivity), and even better bounds hold for planar graphs with minimum…

Discrete Mathematics · Computer Science 2020-02-21 Therese Biedl , John Wittnebel

Given an n-vertex graph G, a drawing of G in the plane is a mapping of its vertices into points of the plane, and its edges into continuous curves, connecting the images of their endpoints. A crossing in such a drawing is a point where two…

Data Structures and Algorithms · Computer Science 2010-10-20 Julia Chuzhoy , Yury Makarychev , Anastasios Sidiropoulos

Let $G$ be a multigraph with $n$ vertices and $e>4n$ edges, drawn in the plane such that any two parallel edges form a simple closed curve with at least one vertex in its interior and at least one vertex in its exterior. Pach and T\'oth (A…

Combinatorics · Mathematics 2021-10-20 Michael Kaufmann , Janos Pach , Geza Toth , Torsten Ueckerdt

In this paper, we investigate crossing-free 3D morphs between planar straight-line drawings. We show that, for any two (not necessarily topologically equivalent) planar straight-line drawings of an $n$-vertex planar graph, there exists a…

Computational Geometry · Computer Science 2025-03-03 Kevin Buchin , Will Evans , Fabrizio Frati , Irina Kostitsyna , Maarten Löffler , Tim Ophelders , Alexander Wolff

We study the following classes of beyond-planar graphs: 1-planar, IC-planar, and NIC-planar graphs. These are the graphs that admit a 1-planar, IC-planar, and NIC-planar drawing, respectively. A drawing of a graph is 1-planar if every edge…

Computational Geometry · Computer Science 2019-08-12 Steven Chaplick , Fabian Lipp , Alexander Wolff , Johannes Zink

A graph drawn in the plane with n vertices is k-fan-crossing free for k > 1 if there are no k+1 edges $g,e_1,...e_k$, such that $e_1,e_2,...e_k$ have a common endpoint and $g$ crosses all $e_i$. We prove a tight bound of 4n-8 on the maximum…

Computational Geometry · Computer Science 2013-11-11 Otfried Cheong , Sariel Har-Peled , Heuna Kim , Hyo-Sil Kim

A visibility representation is a classical drawing style of planar graphs. It displays the vertices of a graph as horizontal vertex-segments, and each edge is represented by a vertical edge-segment touching the segments of its end vertices;…

Computational Geometry · Computer Science 2013-08-26 Franz J. Brandenburg

A topological graph is $k$-quasi-planar if it does not contain $k$ pairwise crossing edges. A 20-year-old conjecture asserts that for every fixed $k$, the maximum number of edges in a $k$-quasi-planar graph on $n$ vertices is $O(n)$. Fox…

Combinatorics · Mathematics 2016-01-28 Andrew Suk , Bartosz Walczak

We study 3-plane drawings, that is, drawings of graphs in which every edge has at most three crossings. We show how the recently developed Density Formula for topological drawings of graphs (KKKRSU GD 2024) can be used to count the…

Combinatorics · Mathematics 2025-03-12 Miriam Goetze , Michael Hoffmann , Ignaz Rutter , Torsten Ueckerdt

We introduce the triple crossing number, a variation of crossing number, of a graph, which is the minimal number of crossing points in all drawings with only triple crossings of the graph. It is defined to be zero for a planar graph, and to…

Combinatorics · Mathematics 2012-01-16 Hiroyuki Tanaka , Masakazu Teragaito

An octilinear drawing of a planar graph is one in which each edge is drawn as a sequence of horizontal, vertical and diagonal at 45 degrees line-segments. For such drawings to be readable, special care is needed in order to keep the number…

Computational Geometry · Computer Science 2015-12-16 Michael A. Bekos , Michael Kaufmann , Robert Krug

A topological graph is \emph{$k$-quasi-planar} if it does not contain $k$ pairwise crossing edges. A topological graph is \emph{simple} if every pair of its edges intersect at most once (either at a vertex or at their intersection). In…

Combinatorics · Mathematics 2015-03-19 Andrew Suk

We study $c$-crossing-critical graphs, which are the minimal graphs that require at least $c$ edge-crossings when drawn in the plane. For $c=1$ there are only two such graphs without degree-2 vertices, $K_5$ and $K_{3,3}$, but for any fixed…

Combinatorics · Mathematics 2026-05-08 Zdeněk Dvořák , Petr Hliněný , Bojan Mohar

An outer-1-planar graph is a graph admitting a drawing in the plane so that all vertices appear in the outer region of the drawing and every edge crosses at most one other edge. This paper establishes the local structure of outer-1-planar…

Combinatorics · Mathematics 2023-06-22 Yan Li , Xin Zhang