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Related papers: On treewidth and maximum cliques

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Given an undirected $n$-vertex graph $G(V,E)$ and an integer $k$, let $T_k(G)$ denote the random vertex induced subgraph of $G$ generated by ordering $V$ according to a random permutation $\pi$ and including in $T_k(G)$ those vertices with…

Discrete Mathematics · Computer Science 2018-01-29 Uriel Feige , Jonathan Hermon , Daniel Reichman

In this paper, we relate the seemingly unrelated concepts of treewidth and boxicity. Our main result is that, for any graph G, boxicity(G) <= treewidth(G) + 2. We also show that this upper bound is (almost) tight. Our result leads to…

Combinatorics · Mathematics 2007-05-23 L. Sunil Chandran , Naveen Sivadasan

A bound on consecutive clique numbers of graphs is established. This bound is evaluated and shown to often be much better than the bound of the Kruskal-Katona theorem. A bound on non-consecutive clique numbers is also proven.

Combinatorics · Mathematics 2007-10-23 Andy Frohmader

A class of graphs is bridge-addable if given a graph $G$ in the class, any graph obtained by adding an edge between two connected components of $G$ is also in the class. We prove a conjecture of McDiarmid, Steger, and Welsh, that says that…

Combinatorics · Mathematics 2023-06-23 Guillaume Chapuy , Guillem Perarnau

This paper considers limit theorems associated with subgraph counts in the age-dependent random connection model. First, we identify regimes where the count of sub-trees converges weakly to a stable random variable under suitable…

Probability · Mathematics 2024-09-10 Christian Hirsch , Takashi Owada

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

An independent set in a graph is a set of pairwise non-adjacent vertices. The independence number $\alpha{(G)}$ is the size of a maximum independent set in the graph $G$. The independence polynomial of a graph is the generating function for…

Discrete Mathematics · Computer Science 2022-03-08 Ron Yosef , Matan Mizrachi , Ohr Kadrawi

We introduce the notion of delineation. A graph class $\mathcal C$ is said delineated if for every hereditary closure $\mathcal D$ of a subclass of $\mathcal C$, it holds that $\mathcal D$ has bounded twin-width if and only if $\mathcal D$…

Data Structures and Algorithms · Computer Science 2022-04-05 Édouard Bonnet , Dibyayan Chakraborty , Eun Jung Kim , Noleen Köhler , Raul Lopes , Stéphan Thomassé

We study set systems formed by neighborhoods in graphs of bounded twin-width. We start by proving that such graphs have linear neighborhood complexity, in analogy to previous results concerning graphs from classes with bounded expansion and…

Logic in Computer Science · Computer Science 2023-04-27 Wojciech Przybyszewski

We generalize two main theorems of matching polynomials of undirected simple graphs, namely, real-rootedness and the Heilmann-Lieb root bound. Viewing the matching polynomial of a graph $G$ as the independence polynomial of the line graph…

Combinatorics · Mathematics 2019-02-20 Jonathan Leake , Nick Ryder

Probabilistic graphical models offer a powerful framework to account for the dependence structure between variables, which is represented as a graph. However, the dependence between variables may render inference tasks intractable. In this…

Courcelle's celebrated theorem states that all MSO-expressible properties can be decided in linear time on graphs of bounded treewidth. Unfortunately, the hidden constant implied by this theorem is a tower of exponentials whose height…

Data Structures and Algorithms · Computer Science 2026-05-04 Michael Lampis

To each link $L$ in $S^3$ we associate a collection of certain labelled directed trees, called width trees. We interpret some classical and new topological link invariants in terms of these width trees and show how the geometric structure…

Geometric Topology · Mathematics 2021-09-28 Qidong He , Scott A. Taylor

We propose and study a hierarchical algorithm to generate graphs having a predetermined distribution of cliques, the fully connected subgraphs. The construction mechanism may be either random or incorporate preferential attachment. We…

Physics and Society · Physics 2009-11-13 Gregor Kaczor , Claudius Gros

We prove that the treewidth of an Erd\"{o}s-R\'{e}nyi random graph $\rg{n, m}$ is, with high probability, greater than $\beta n$ for some constant $\beta > 0$ if the edge/vertex ratio $\frac{m}{n}$ is greater than 1.073. Our lower bound…

Discrete Mathematics · Computer Science 2009-08-03 Yong Gao

In this article we study the treewidth of the \emph{display graph}, an auxiliary graph structure obtained from the fusion of phylogenetic (i.e., evolutionary) trees at their leaves. Earlier work has shown that the treewidth of the display…

Discrete Mathematics · Computer Science 2017-04-03 Steven Kelk , Georgios Stamoulis , Taoyang Wu

A $P_4$ is a chordless path on four vertices. A diamond is a graph obtained from a clique of size four by removing one edge of the clique. A paw is a graph obtained from a clique of size four by removing two adjacent edges of the clique. We…

Discrete Mathematics · Computer Science 2026-05-18 Paweł Rafał Bieliński , Jadwiga Czyżewska , Martin Milanič , Amir Nikabadi , Paweł Rzążewski

A contraction sequence of a graph consists of iteratively merging two of its vertices until only one vertex remains. The recently introduced twin-width graph invariant is based on contraction sequences. More precisely, if one puts red edges…

Data Structures and Algorithms · Computer Science 2022-06-02 Édouard Bonnet , Eun Jung Kim , Amadeus Reinald , Stéphan Thomassé

We investigate clique trees of infinite locally finite chordal graphs. Our main contribution is a bijection between the set of clique trees and the product of local finite families of finite trees. Even more, the edges of a clique tree are…

Combinatorics · Mathematics 2018-03-23 Christoph Hofer-Temmel , Florian Lehner

A graph is locally chordal if each of its small-radius balls is chordal. In an earlier work [AKK25], the authors and Kobler proved that locally chordal graphs can be characterized by having chordal local covers, by forbidding short cycles…

Combinatorics · Mathematics 2025-12-23 Tara Abrishami , Paul Knappe