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Related papers: Well-quasi-ordered classes of bounded clique-width

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We prove that every class of graphs $\mathscr C$ that is monadically stable and has bounded twin-width can be transduced from some class with bounded sparse twin-width. This generalizes analogous results for classes of bounded linear…

Logic in Computer Science · Computer Science 2022-09-20 Jakub Gajarský , Michał Pilipczuk , Szymon Toruńczyk

In this paper, we characterise graphs that are quasi-isometric to graphs with bounded treewidth. Specifically, we prove that a graph is quasi-isometric to a graph with bounded treewidth if and only if it has a tree-decomposition where each…

Combinatorics · Mathematics 2025-08-21 Robert Hickingbotham

A graph is said to be well-covered if all its maximal independent sets are of the same size. In 1999, Yamashita and Kameda introduced a subclass of well-covered graphs, called localizable graphs and defined as graphs having a partition of…

Combinatorics · Mathematics 2017-01-09 Ademir Hujdurović , Martin Milanič , Bernard Ries

We study the complexity of the Graph Isomorphism problem on graph classes that are characterized by a finite number of forbidden induced subgraphs, focusing mostly on the case of two forbidden subgraphs. We show hardness results and develop…

Data Structures and Algorithms · Computer Science 2015-03-20 Stefan Kratsch , Pascal Schweitzer

We study some properties of graphs (or, rather, graph sequences) defined by demanding that the number of subgraphs of a given type, with vertices in subsets of given sizes, approximatively equals the number expected in a random graph. It…

Combinatorics · Mathematics 2014-05-28 Svante Janson , Vera T. Sós

Given two graphs $H_1$ and $H_2$, a graph $G$ is $(H_1,H_2)$-free if it contains no subgraph isomorphic to $H_1$ or $H_2$. We continue a recent study into the clique-width of $(H_1,H_2)$-free graphs and present three new classes of…

Discrete Mathematics · Computer Science 2015-01-14 Konrad K. Dabrowski , Shenwei Huang , Daniël Paulusma

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

We continue the study of $(tw,\omega)$-bounded graph classes, that is, hereditary graph classes in which large treewidth is witnessed by the presence of a large clique, and the relation of this property to boundedness of the…

Combinatorics · Mathematics 2025-05-20 Claire Hilaire , Martin Milanič , Đorđe Vasić

The juxtaposition of permutation classes $\mathcal{C}$ and $\mathcal{D}$ is the class of all permutations formed by concatenations $\sigma\tau$, such that $\sigma$ is order isomorphic to a permutation in $\mathcal{C}$, and $\tau$ to a…

Combinatorics · Mathematics 2023-12-20 Robert Brignall

A graph is said to be well-dominated if all its minimal dominating sets are of the same size. The class of well-dominated graphs forms a subclass of the well studied class of well-covered graphs. While the recognition problem for the class…

Discrete Mathematics · Computer Science 2023-06-22 Didem Gözüpek , Ademir Hujdurović , Martin Milanič

We prove some results concerning Alcuin number of graphs. First, we classify graphs which have unique minimum vertex cover. Then we present two necessary conditions for a graph to be of class two and show why one of them (condition on…

Combinatorics · Mathematics 2014-09-25 Abbas Seify , Hossein Shahmohamad

A large number of NP-hard graph problems become polynomial-time solvable on graph classes where the mim-width is bounded and quickly computable. Hence, when solving such problems on special graph classes, it is helpful to know whether the…

Data Structures and Algorithms · Computer Science 2021-08-27 Nick Brettell , Jake Horsfield , Andrea Munaro , Giacomo Paesani , Daniel Paulusma

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

We generalize the notion of quasirandom which concerns a class of equivalent properties that random graphs satisfy. We show that the convergence of a graph sequence under the spectral distance is equivalent to the convergence using the…

Combinatorics · Mathematics 2013-11-06 Fan Chung

Although the chromatic number of a graph is not known in general, attempts have been made to find good bounds for the number. Here we prove that for a graph G with two forbidden subgraphs and maximum degree less than or equal to 2{\omega} -…

Combinatorics · Mathematics 2016-05-11 Medha Dhurandhar

The class of closed graphs by a linear ordering on their sets of vertices is investigated. A recent characterization of such a class of graphs is analyzed by using tools from the proper interval graph theory.

Combinatorics · Mathematics 2015-09-23 Marilena Crupi

Suppose a graph has no large balanced bicliques, but has large minimum degree. Then what can we say about its induced subgraphs? This question motivates the study of degree-boundedness, which is like $\chi$-boundedness but for minimum…

Combinatorics · Mathematics 2024-11-14 Xiying Du , Rose McCarty

In 2006 Qian [J. Qian, Degree complete graphs; Discrete Mathematics 306 (2006), 533--537] introduced the concept of degree complete graphs for labeled graphs. He also gave a characterization of these graphs in terms of two forbidden…

Combinatorics · Mathematics 2017-06-15 Sebastian Milz

Motivated by the question of whether planar graphs have bounded queue-number, we prove that planar graphs with maximum degree $\Delta$ have queue-number $O(\Delta^{2})$, which improves upon the best previous bound of $O(\Delta^6)$. More…

Combinatorics · Mathematics 2019-05-31 Vida Dujmović , Pat Morin , David R. Wood

The sparsity order of a (simple undirected) graph is the highest possible rank (over ${\mathbb R}$ or ${\mathbb C}$) of the extremal elements in the matrix cone that consists of positive semidefinite matrices with prescribed zeros on the…

Functional Analysis · Mathematics 2020-02-21 S. ter Horst , E. M. Klem