English
Related papers

Related papers: Planar graphs have bounded queue-number

200 papers

Aboulker, Adler, Kim, Sintiari, and Trotignon conjectured that every graph with bounded maximum degree and large treewidth must contain, as an induced subgraph, a large subdivided wall, or the line graph of a large subdivided wall. This…

Combinatorics · Mathematics 2022-05-19 Bogdan Alecu , Maria Chudnovsky , Kristina Vušković

We establish that a simple polynomial-time algorithm that we call reweighted spectral partitioning obtains small 2/3-balanced vertex-separators for a number of graph classes, including $O(\sqrt{n})$-sized separators for planar graphs,…

Data Structures and Algorithms · Computer Science 2025-11-18 Jack Spalding-Jamieson

We prove that if the prime graphs in a graph class have bounded lettericity, then the entire class has bounded lettericity if and only if it does not contain arbitrary large matchings, co-matchings, or a family of graphs that we call…

Combinatorics · Mathematics 2021-11-17 Robert Ferguson , Vincent Vatter

Shrub-depth and rank-depth are dense analogues of the tree-depth of a graph. It is well known that a graph has large tree-depth if and only if it has a long path as a subgraph. We prove an analogous statement for shrub-depth and rank-depth,…

Combinatorics · Mathematics 2022-10-05 O-joung Kwon , Rose McCarty , Sang-il Oum , Paul Wollan

A graph is a split graph if its vertex set can be partitioned into a clique and a stable set. A split graph is unbalanced if there exist two such partitions that are distinct. Cheng, Collins and Trenk (2016), discovered the following…

Combinatorics · Mathematics 2017-06-13 Karen L. Collins , Ann N. Trenk

We introduce a new subclass of chordal graphs that generalizes split graphs, which we call well-partitioned chordal graphs. Split graphs are graphs that admit a partition of the vertex set into cliques that can be arranged in a star…

Combinatorics · Mathematics 2020-02-26 Jungho Ahn , Lars Jaffke , O-joung Kwon , Paloma T. Lima

An $h$-queue layout of a graph $G$ consists of a linear order of its vertices and a partition of its edges into $h$ queues, such that no two independent edges of the same queue nest. The minimum $h$ such that $G$ admits an $h$-queue layout…

Computational Geometry · Computer Science 2020-08-20 Sujoy Bhore , Robert Ganian , Fabrizio Montecchiani , Martin Nöllenburg

A circle graph is an intersection graph of a set of chords of a circle. We describe the unavoidable induced subgraphs of circle graphs with large treewidth. This includes examples that are far from the `usual suspects'. Our results imply…

Combinatorics · Mathematics 2022-12-23 Robert Hickingbotham , Freddie Illingworth , Bojan Mohar , David R. Wood

We continue the study of linear layouts of graphs in relation to known data structures. At a high level, given a data structure, the goal is to find a linear order of the vertices of the graph and a partition of its edges into pages, such…

Data Structures and Algorithms · Computer Science 2022-09-02 Michael A. Bekos , Stefan Felsner , Philipp Kindermann , Stephen Kobourov , Jan Kratovíl , Ignaz Rutter

We discover new hereditary classes of graphs that are minimal (with respect to set inclusion) of unbounded clique-width. The new examples include split permutation graphs and bichain graphs. Each of these classes is characterised by a…

Combinatorics · Mathematics 2023-01-31 A. Atminas , R. Brignall , V. Lozin , J. Stacho

The maximum number of vertices in a graph of maximum degree $\Delta\ge 3$ and fixed diameter $k\ge 2$ is upper bounded by $(1+o(1))(\Delta-1)^{k}$. If we restrict our graphs to certain classes, better upper bounds are known. For instance,…

Combinatorics · Mathematics 2015-12-14 Eran Nevo , Guillermo Pineda-Villavicencio , David R. Wood

A long-standing question of the mutual relation between the stack and queue numbers of a graph, explicitly emphasized by Dujmovi\'c and Wood in 2005, was "half-answered" by Dujmovi\'c, Eppstein, Hickingbotham, Morin and Wood in 2022; they…

Combinatorics · Mathematics 2024-11-19 Petr Hliněný , Adam Straka

We prove that a hereditary class of graphs is $(\mathsf{tw}, \omega)$-bounded if and only if the induced minors of the graphs from the class form a $(\mathsf{tw}, \omega)$-bounded class.

Combinatorics · Mathematics 2024-10-24 Claire Hilaire , Martin Milanič , Nicolas Trotignon , Djordje Vasić

We study separating systems of the edges of a graph where each member of the separating system is a path. We conjecture that every $n$-vertex graph admits a separating path system of size $O(n)$ and prove this in certain interesting special…

Linear rank-width is a graph width parameter, which is a variation of rank-width by restricting its tree to a caterpillar. As a corollary of known theorems, for each $k$, there is a finite obstruction set $\mathcal{O}_k$ of graphs such that…

Combinatorics · Mathematics 2014-09-10 Jisu Jeong , O-joung Kwon , Sang-il Oum

We study two notions of being well-structured for classes of graphs that are inspired by classic model theory. A class of graphs $C$ is monadically stable if it is impossible to define arbitrarily long linear orders in vertex-colored graphs…

Discrete Mathematics · Computer Science 2020-07-16 Jaroslav Nesetril , Patrice Ossona de Mendez , Michal Pilipczuk , Roman Rabinovich , Sebastian Siebertz

In the first paper of the Graph Minors series [JCTB '83], Robertson and Seymour proved the Forest Minor theorem: the $H$-minor-free graphs have bounded pathwidth if and only if $H$ is a forest. In recent years, considerable effort has been…

Combinatorics · Mathematics 2025-12-02 Édouard Bonnet , Benjamin Duhamel , Robert Hickingbotham

The bondage number of a graph is the smallest number of its edges whose removal results in a graph having a larger domination number. We provide constant upper bounds for the bondage number of graphs on topological surfaces, improve upper…

Combinatorics · Mathematics 2014-07-08 Andrei Gagarin , Vadim Zverovich

Archdeacon (1987) proved that graphs embeddable on a fixed surface can be $3$-coloured so that each colour class induces a subgraph of bounded maximum degree. Edwards, Kang, Kim, Oum and Seymour (2015) proved that graphs with no…

Combinatorics · Mathematics 2019-07-15 Patrice Ossona de Mendez , Sang-il Oum , David R. Wood

An ordered graph is a graph with a linear ordering on its vertex set. We prove that for every positive integer $k$, there exists a constant $c_k>0$ such that any ordered graph $G$ on $n$ vertices with the property that neither $G$ nor its…

Combinatorics · Mathematics 2020-04-10 János Pach , István Tomon