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Related papers: Twin-width IV: ordered graphs and matrices

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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

The celebrated theorem of Robertson and Seymour states that in the family of minor-closed graph classes, there is a unique minimal class of graphs of unbounded tree-width, namely, the class of planar graphs. In the case of tree-width, the…

Combinatorics · Mathematics 2017-02-01 A. Collins , J. Foniok , N. Korpelainen , V. Lozin , V. Zamaraev

We introduce a new parameter, called stretch-width, that we show sits strictly between clique-width and twin-width. Unlike the reduced parameters [BKW '22], planar graphs and polynomial subdivisions do not have bounded stretch-width. This…

Discrete Mathematics · Computer Science 2023-05-23 Édouard Bonnet , Julien Duron

Recently, the saturation problem of $0$-$1$ matrices gained a lot of attention. This problem can be regarded as a saturation problem of ordered bipartite graphs. Motivated by this, we initiate the study of the saturation problem of ordered…

Combinatorics · Mathematics 2022-03-11 Vladimir Bošković , Balázs Keszegh

We give essentially tight bounds for, $\nu(d,k)$, the maximum number of distinct neighbourhoods on a set $X$ of $k$ vertices in a graph with twin-width at most~$d$. Using the celebrated Marcus-Tardos theorem, two independent works [Bonnet…

Combinatorics · Mathematics 2023-08-08 Édouard Bonnet , Florent Foucaud , Tuomo Lehtilä , Aline Parreau

An ordered matching of size $n$ is a graph on a linearly ordered vertex set $V$, $|V|=2n$, consisting of $n$ pairwise disjoint edges. There are three different ordered matchings of size two on $V=\{1,2,3,4\}$: an alignment…

Combinatorics · Mathematics 2024-04-25 Andrzej Dudek , Jarosław Grytczuk , Andrzej Ruciński

Balogh, Bollob\'{a}s and Morris (2006) have described a threshold phenomenon in the behavior of the profile of hereditary classes of ordered graphs. In this paper, we give an other look at their result based on the notion of monomorphic…

Combinatorics · Mathematics 2019-01-29 Djamila Oudrar

We study subclasses of grid intersection graphs from the perspective of order dimension. We show that partial orders of height two whose comparability graph is a grid intersection graph have order dimension at most four. Starting from this…

Combinatorics · Mathematics 2015-12-09 Steven Chaplick , Stefan Felsner , Udo Hoffmann , Veit Wiechert

Twin-width is a graph width parameter recently introduced by Bonnet, Kim, Thomass\'{e} & Watrigant. Given two graphs $G$ and $H$ and a graph product $\star$, we address the question: is the twin-width of $G\star H$ bounded by a function of…

Combinatorics · Mathematics 2024-02-14 William Pettersson , John Sylvester

We prove that a hereditary graph class $\mathcal{G}$ defined by finitely many excluded induced subgraphs has bounded tree-$\alpha$ if and only if it is "$(\mathrm{tw},\omega)$-bounded" (that is, for all $t\in \mathbb N$, the class of all…

Combinatorics · Mathematics 2026-05-05 Sepehr Hajebi , Sophie Spirkl

It is known that any planar graph with diameter D has treewidth O(D), and this fact has been used as the basis for several planar graph algorithms. We investigate the extent to which similar relations hold in other graph families. We show…

Combinatorics · Mathematics 2010-01-21 David Eppstein

We provide a doubly exponential upper bound in $p$ on the size of forbidden pivot-minors for symmetric or skew-symmetric matrices over a fixed finite field $\mathbb{F}$ of linear rank-width at most $p$. As a corollary, we obtain a doubly…

Combinatorics · Mathematics 2014-12-24 Mamadou Moustapha Kanté , O-joung Kwon

Given an infinite word over the alphabet $\{0,1,2,3\}$, we define a class of bipartite hereditary graphs $\mathcal{G}^\alpha$, and show that $\mathcal{G}^\alpha$ has unbounded clique-width unless $\alpha$ contains at most finitely many…

Combinatorics · Mathematics 2023-11-08 Robert Brignall , Daniel Cocks

The fascinating question of the maximum value of twin-width on planar graphs is nowadays not far from the final resolution; there is a lower bound of 7 coming from a construction by Kr\'al' and Lamaison [arXiv, September 2022], and an upper…

Combinatorics · Mathematics 2024-07-03 Petr Hliněný

A graph $H$ is an induced subgraph of a graph $G$ if a graph isomorphic to $H$ can be obtained from $G$ by deleting vertices. Recently, there has been significant interest in understanding the unavoidable induced subgraphs for graphs of…

Combinatorics · Mathematics 2022-07-01 Robert Hickingbotham

In this article, we study "questionable representations" of (partial or total) orders, introduced in our previous article "A class of orders with linear? time sorting algorithm". (Later, we consider arbitrary binary functional/relational…

Combinatorics · Mathematics 2020-02-24 Laurent Lyaudet

In the companion paper [Linear rank-width of distance-hereditary graphs I. A polynomial-time algorithm, Algorithmica 78(1):342--377, 2017], we presented a characterization of the linear rank-width of distance-hereditary graphs, from which…

Combinatorics · Mathematics 2017-08-16 Mamadou Moustapha Kanté , O-joung Kwon

We show that every graph with twin-width $t$ has chromatic number $O(\omega ^{k_t})$ for some integer $k_t$, where $\omega$ denotes the clique number. This extends a quasi-polynomial bound from Pilipczuk and Soko{\l}owski and generalizes a…

Discrete Mathematics · Computer Science 2025-01-20 Romain Bourneuf , Stéphan Thomassé

For classes O of structures on finite linear orders (permutations, ordered graphs etc.) endowed with containment order cont (containment of permutations, subgraph relation etc.), we investigate restrictions on the function f(n) counting…

Combinatorics · Mathematics 2007-05-23 Martin Klazar

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