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Related papers: Shrub-depth: Capturing Height of Dense Graphs

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We present a concept called the branch-depth of a connectivity function, that generalizes the tree-depth of graphs. Then we prove two theorems showing that this concept aligns closely with the notions of tree-depth and shrub-depth of graphs…

Combinatorics · Mathematics 2020-11-05 Matt DeVos , O-joung Kwon , Sang-il Oum

In a recent paper, Kwon and Oum claim that every graph of bounded rank-width is a pivot-minor of a graph of bounded tree-width (while the converse has been known true already before). We study the analogous questions for "depth" parameters…

Discrete Mathematics · Computer Science 2014-03-28 Petr Hliněný , O-joung Kwon , Jan Obdržálek , Sebastian Ordyniak

The treewidth of a graph is an important invariant in structural and algorithmic graph theory. This paper studies the treewidth of line graphs. We show that determining the treewidth of the line graph of a graph $G$ is equivalent to…

Combinatorics · Mathematics 2014-09-25 Daniel J. Harvey , David R. Wood

Shrub-depth and rank-depth are dense analogues of the tree-depth of a graph. It is well known that a graph has large tree-depth if and only if it has a long path as a subgraph. We prove an analogous statement for shrub-depth and rank-depth,…

Combinatorics · Mathematics 2022-10-05 O-joung Kwon , Rose McCarty , Sang-il Oum , Paul Wollan

The tree-depth is a parameter introduced under several names as a measure of sparsity of a graph. We compute asymptotic values of the tree-depth of random graphs. For dense graphs, p>> 1/n, the tree-depth of a random graph G is a.a.s.…

Combinatorics · Mathematics 2012-02-16 Guillem Perarnau , Oriol Serra

The theory of sparse structures usually uses tree like structures as building blocks. In the context of sparse/dense dichotomy this role is played by graphs with bounded tree depth. In this paper we survey results related to this concept…

Combinatorics · Mathematics 2016-08-09 Jaroslav Nesetril , Patrice Ossona De Mendez

Graph transformations definable in logic can be described using the notion of transductions. By understanding transductions as a basic embedding mechanism, which captures the possibility of encoding one graph in another graph by means of…

Combinatorics · Mathematics 2025-01-09 Michał Pilipczuk

Tree-width has been proven to be a useful parameter to design fast and efficient algorithms for intractable problems. However, while tree-width is low on relatively sparse graphs can be arbitrary high on dense graphs. Therefore, we…

Data Structures and Algorithms · Computer Science 2021-11-04 Chris Aronis

Cliquewidth is a dense analogue of treewidth. It can be deduced from recent results by Hickingbotham [arXiv:2501.10840] and Nguyen, Scott, and Seymour [arXiv:2501.09839] that graphs of bounded cliquewidth are quasi-isometric to graphs of…

Combinatorics · Mathematics 2025-05-26 Marc Distel

A connected graph has tree-depth at most $k$ if it is a subgraph of the closure of a rooted tree whose height is at most $k$. We give an algorithm which for a given $n$-vertex graph $G$, in time $\mathcal{O}(1.9602^n)$ computes the…

Data Structures and Algorithms · Computer Science 2013-06-18 Fedor V. Fomin , Archontia C. Giannopoulou , Michał Pilipczuk

Dynamic programming on various graph decompositions is one of the most fundamental techniques used in parameterized complexity. Unfortunately, even if we consider concepts as simple as path or tree decompositions, such dynamic programming…

Transductions are a general formalism for expressing transformations of graphs (and more generally, of relational structures) in logic. We prove that a graph class $\mathscr{C}$ can be $\mathsf{FO}$-transduced from a class of bounded-height…

Combinatorics · Mathematics 2022-04-01 Michał Pilipczuk , Patrice Ossona de Mendez , Sebastian Siebertz

The graph parameter shrub-depth is a dense analog of tree-depth. We characterize classes of bounded shrub-depth by forbidden induced subgraphs. The obstructions are well-controlled flips of large half-graphs and of disjoint unions of many…

Logic in Computer Science · Computer Science 2025-01-24 Nikolas Mählmann

Treedepth, a more restrictive graph width parameter than treewidth and pathwidth, plays a major role in the theory of sparse graph classes. We show that there exists a constant $C$ such that for every positive integers $a,b$ and a graph…

Discrete Mathematics · Computer Science 2019-09-19 Wojciech Czerwiński , Wojciech Nadara , Marcin Pilipczuk

Dynamic graph theory is a novel, growing area that deals with graphs that change over time and is of great utility in modelling modern wireless, mobile and dynamic environments. As a graph evolves, possibly arbitrarily, it is challenging to…

Computational Complexity · Computer Science 2012-05-28 Bernard Mans , Luke Mathieson

The study of structural graph width parameters like tree-width, clique-width and rank-width has been ongoing during the last five decades, and their algorithmic use has also been increasing [Cygan et al., 2015]. New width parameters…

Data Structures and Algorithms · Computer Science 2025-01-23 Flavia Bonomo-Braberman , Eric Brandwein , Carolina Lucía González , Agustín Sansone

We give new decomposition theorems for classes of graphs that can be transduced in first-order logic from classes of sparse graphs -- more precisely, from classes of bounded expansion and from nowhere dense classes. In both cases, the…

Logic in Computer Science · Computer Science 2022-01-27 Jan Dreier , Jakub Gajarský , Sandra Kiefer , Michał Pilipczuk , Szymon Toruńczyk

The twin-width of a graph measures its distance to co-graphs and generalizes classical width concepts such as tree-width or rank-width. Since its introduction in 2020 (Bonnet et. al. 2020), a mass of new results has appeared relating twin…

Combinatorics · Mathematics 2024-11-21 Irene Heinrich , Simon Raßmann

Tree-width is an invaluable tool for computational problems on graphs. But often one would like to compute on other kinds of objects (e.g. decorated graphs or even algebraic structures) where there is no known tree-width analogue. Here we…

Combinatorics · Mathematics 2022-06-22 Benjamin Merlin Bumpus , Zoltan A. Kocsis

Treewidth is a well-known graph invariant with multiple interesting applications in combinatorics. On the practical side, many NP-complete problems are polynomial-time (sometimes even linear-time) solvable on graphs of bounded treewidth. On…

Category Theory · Mathematics 2021-05-13 Zoltan A. Kocsis , Benjamin Merlin Bumpus
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