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Related papers: A dichotomy for graphs of bounded degeneracy

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A hereditary class H of graphs is $\chi$-bounded if there is a $\chi$-binding function f such that for every $G$ in $H$, $\chi(G)$ less than or equal to $f(\omega(G))$. Here we prove that if a graph $G$ is free of 1. {Chair; P$_4$+K$_1$} or…

Combinatorics · Mathematics 2023-12-29 Medha Dhurandhar

An $acyclic$ edge coloring of a graph is a proper edge coloring such that there are no bichromatic cycle s. The \emph{acyclic chromatic index} of a graph is the minimum number k such that there is an acyclic e dge coloring using k colors…

Combinatorics · Mathematics 2008-10-20 Manu Basavaraju , L. Sunil Chandran

The tree-independence number of a graph is the minimum, over all tree-decompositions of the graph, of the maximum size of an independent set contained in a bag. Graph classes of bounded tree-independence number have strong structural and…

We prove that there is an algorithm to determine if a given finite graph is an induced subgraph of a given curve graph.

Geometric Topology · Mathematics 2017-02-17 Tarik Aougab , Ian Biringer , Jonah Gaster

We show that if a subset $\Psi$ of the ends of a graph $G$ can be displayed by a tree-decomposition of finite adhesion, then it can also be displayed by a linked such tree-decomposition. This tree-decomposition captures all combinatorial…

Combinatorics · Mathematics 2025-12-16 Sandra Albrechtsen , Max Pitz , Roman Schaut

We show that for any $d\ge 2$ and $\Delta>0$ there exists $\eta>0$ such that the following holds: Let $G$ be an $n$-vertex graph with at least $\Omega(n^2)$ edges and let $H$ be an $n$-vertex $d$-degenerate graph with maximum degree at most…

Combinatorics · Mathematics 2026-02-26 Jie Han , Seonghyuk Im , Bin Wang , Junxue Zhang

Daligault, Rao and Thomass\'e asked whether a hereditary class of graphs well-quasi-ordered by the induced subgraph relation has bounded clique-width. Lozin, Razgon and Zamaraev recently showed that this is not true for classes defined by…

Combinatorics · Mathematics 2016-11-14 Konrad K. Dabrowski , Vadim V. Lozin , Daniël Paulusma

We consider hereditary classes of graphs equipped with a total order. We provide multiple equivalent characterisations of those classes which have bounded twin-width. In particular, we prove a grid theorem for classes of ordered graphs…

Logic in Computer Science · Computer Science 2021-07-07 Pierre Simon , Szymon Toruńczyk

We give a unified approach to analysing, for each positive integer $s$, a class of finite connected graphs that contains all the distance transitive graphs as well as the locally $s$-arc transitive graphs of diameter at least $s$. A graph…

Combinatorics · Mathematics 2010-10-29 Alice Devillers , Michael Giudici , Cai Heng Li , Cheryl E. Praeger

It is well-known that the graphs not containing a given graph H as a subgraph have bounded chromatic number if and only if H is acyclic. Here we consider ordered graphs, i.e., graphs with a linear ordering on their vertex set, and the…

Combinatorics · Mathematics 2016-03-02 Maria Axenovich , Jonathan Rollin , Torsten Ueckerdt

We prove a conjecture of Bonamy, Bousquet, Pilipczuk, Rz\k{a}\.zewski, Thomass\'e, and Walczak, that for every graph $H$, there is a polynomial $p$ such that for every positive integer $s$, every graph of average degree at least $p(s)$…

Combinatorics · Mathematics 2024-09-30 Romain Bourneuf , Matija Bucić , Linda Cook , James Davies

We introduce pathographs as a framework to study graph classes defined by forbidden structures, including forbidding induced subgraphs, minors, etc. Pathographs approximately generalize s-graphs of L\'ev\^eque--Lin--Maffray--Trotignon by…

Combinatorics · Mathematics 2025-05-27 Daniel Carter , Nicolas Trotignon

Our main result is a full classification, for every connected graph $H$, of the computational complexity of Steiner Forest on $H$-subgraph-free graphs. To obtain this dichotomy, we establish the following new algorithmic, hardness, and…

In this paper, we give sharp upper and lower bounds for the number of degenerate monic (and arbitrary, not necessarily monic) polynomials with integer coefficients of fixed degree $n \ge 2$ and height bounded by $H \ge 2$. The polynomial is…

Number Theory · Mathematics 2015-01-14 Artūras Dubickas , Min Sha

We say that a graph $H$ dominates another graph $H'$ if the number of homomorphisms from $H'$ to any graph $G$ is dominated, in an appropriate sense, by the number of homomorphisms from $H$ to $G$. We study the family of dominating graphs,…

Combinatorics · Mathematics 2024-11-27 David Conlon , Joonkyung Lee

Given a graph $H$, we prove that every (theta, prism)-free graph of sufficiently large treewidth contains either a large clique or an induced subgraph isomorphic to $H$, if and only if $H$ is a forest.

Combinatorics · Mathematics 2025-04-08 Tara Abrishami , Bogdan Alecu , Maria Chudnovsky , Sepehr Hajebi , Sophie Spirkl

In the dense graph limit theory, the topology of the set of graphs is defined by the distribution of the subgraphs spanned by finite number of random vertices. Vera T. S\'os proposed a question that if we consider only the number of edges…

Combinatorics · Mathematics 2015-08-21 Endre Csóka

Let $\mathbf G$ be a graphing, that is a Borel graph defined by $d$ measure preserving involutions. We prove that if $\mathbf G$ is {\em treeable} then it arises as the local limit of some sequence $(G_n)_{n\in\mathbb{N}}$ of graphs with…

Combinatorics · Mathematics 2016-01-22 Lucas Hosseini , Patrice Ossona de Mendez

A graph $G$ is $k$-degenerate if it can be transformed into an empty graph by subsequent removals of vertices of degree $k$ or less. We prove that every connected planar graph with average degree $d \ge 2$ has a 4-degenerate induced…

Combinatorics · Mathematics 2013-10-07 Robert Lukoťka , Ján Mazák , Xuding Zhu

Let $A$ be a gentle algebra. For every collection of string and band diagrammes, we consider the constructible subset of the variety of representations containing all modules with this underlying diagramme. We study degenerations of such…

Representation Theory · Mathematics 2026-01-21 Judith Marquardt