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Related papers: Treewidth, Hadwiger Number, and Induced Minors

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For a finite collection of graphs ${\cal F}$, the ${\cal F}$-M-DELETION problem consists in, given a graph $G$ and an integer $k$, deciding whether there exists $S \subseteq V(G)$ with $|S| \leq k$ such that $G \setminus S$ does not contain…

Data Structures and Algorithms · Computer Science 2021-03-12 Julien Baste , Ignasi Sau , Dimitrios M. Thilikos

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

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

It was recently proved that every planar graph is a subgraph of the strong product of a path and a graph with bounded treewidth. This paper surveys generalisations of this result for graphs on surfaces, minor-closed classes, various…

Combinatorics · Mathematics 2021-02-18 Zdeněk Dvořák , Tony Huynh , Gwenaël Joret , Chun-Hung Liu , David R. Wood

Motivated by an induced counterpart of treewidth sparsifiers (i.e., sparse subgraphs keeping the treewidth large) provided by the celebrated Grid Minor theorem of Robertson and Seymour [JCTB '86] or by a classic result of Chekuri and…

Combinatorics · Mathematics 2024-05-24 Édouard Bonnet

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

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

The local tree-width of a graph G=(V,E) is the function ltw^G: N -> N that associates with every natural number r the maximal tree-width of an r-neighborhood in G. Our main graph theoretic result is a decomposition theorem for graphs with…

Combinatorics · Mathematics 2007-05-23 Martin Grohe

The graph parameter treedepth is minor-monotone; hence, the class of graphs with treedepth at most $k$ is minor-closed. By the Graph Minor Theorem, such a class is characterized by a finite set of forbidden minors. A conjecture of…

Discrete Mathematics · Computer Science 2025-12-02 Kolja Kühn

Given an integer $c\in \mathbb{N}$, we say a graph $G$ is $c$-pinched if $G$ does not contain an induced subgraph consisting of $c$ cycles, all going through a single common vertex and otherwise pairwise disjoint and with no edges between…

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

We prove that several natural graph classes have tree-decompositions with minimum width such that each bag has bounded treewidth. For example, every planar graph has a tree-decomposition with minimum width such that each bag has treewidth…

Combinatorics · Mathematics 2025-12-01 Kevin Hendrey , David R. Wood

For a finite collection of graphs ${\cal F}$, the ${\cal F}$-M-DELETION problem consists in, given a graph $G$ and an integer $k$, decide whether there exists $S \subseteq V(G)$ with $|S| \leq k$ such that $G \setminus S$ does not contain…

Data Structures and Algorithms · Computer Science 2021-03-12 Julien Baste , Ignasi Sau , Dimitrios M. Thilikos

We prove that the (divisorial) gonality of a finite connected graph is lower bounded by its treewidth. We show that equality holds for grid graphs and complete multipartite graphs. We prove that the treewidth lower bound also holds for…

Combinatorics · Mathematics 2022-01-04 Josse van Dobben de Bruyn , Dion Gijswijt

One of the fundamental results in graph minor theory is that for every planar graph~$H$, there is a minimum integer~$f(H)$ such that graphs with no minor isomorphic to~$H$ have treewidth at most~$f(H)$. The best known bound for an arbitrary…

Combinatorics · Mathematics 2025-01-06 Meike Hatzel , Chun-Hung Liu , Bruce Reed , Sebastian Wiederrecht

We construct classes of graphs that are variants of the so-called layered wheel. One of their key properties is that while the treewidth is bounded by a function of the clique number, the construction can be adjusted to make the dependance…

Combinatorics · Mathematics 2025-11-04 Maria Chudnovsky , Nicolas Trotignon

The following theorem is proved: For all $k$-connected graphs $G$ and $H$ each with at least $n$ vertices, the treewidth of the cartesian product of $G$ and $H$ is at least $k(n -2k+2)-1$. For $n\gg k$ this lower bound is asymptotically…

Combinatorics · Mathematics 2013-10-02 David R. Wood

The celebrated Erd\H{o}s-P\'{o}sa Theorem, in one formulation, asserts that for every $c\geq 1$, graphs with no subgraph (or equivalently, minor) isomorphic to the disjoint union of $c$ cycles have bounded treewidth. What can we say about…

Combinatorics · Mathematics 2025-03-10 Bogdan Alecu , Maria Chudnovsky , Sepehr Hajebi , Sophie Spirkl

The celebrated grid exclusion theorem states that for every $h$-vertex planar graph $H$, there is a constant $c_{h}$ such that if a graph $G$ does not contain $H$ as a minor then $G$ has treewidth at most $c_{h}$. We are looking for…

Combinatorics · Mathematics 2015-11-10 Jean-Florent Raymond , Dimitrios M. Thilikos

A graph coloring has bounded clustering if each monochromatic component has bounded size. This paper studies such a coloring, where the number of colors depends on an excluded complete bipartite subgraph. This is a much weaker assumption…

Combinatorics · Mathematics 2022-09-29 Chun-Hung Liu , David R. Wood

Butterfly minors are a generalisation of the minor containment relation for undirected graphs to directed graphs. Many results in directed structural graph theory use this notion as a central tool next to directed treewidth, a…

Combinatorics · Mathematics 2025-04-01 Gunwoo Kim , Meike Hatzel , Stephan Kreutzer