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Related papers: Flip-width: Cops and Robber on dense graphs

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Nowhere dense classes of graphs are very general classes of uniformly sparse graphs with several seemingly unrelated characterisations. From an algorithmic perspective, a characterisation of these classes in terms of uniform quasi-wideness,…

Discrete Mathematics · Computer Science 2018-09-06 Stephan Kreutzer , Roman Rabinovich , Sebastian Siebertz

The game of Cops and Robbers on graphs is a well-studied pursuit--evasion model whose central parameter, the cop number, captures the minimum number of pursuers required to guarantee capture of an adversary on a given graph. While the cop…

Combinatorics · Mathematics 2025-10-09 Nicholas Crawford , Vesna Iršič Chenoweth

The notion of bounded expansion captures uniform sparsity of graph classes and renders various algorithmic problems that are hard in general tractable. In particular, the model-checking problem for first-order logic is fixed-parameter…

We present a framework to define a large class of neural networks for which, by construction, training by gradient flow provably reaches arbitrarily low loss when the number of parameters grows. Distinct from the fixed-space global…

Optimization and Control · Mathematics 2025-01-13 David A. R. Robin , Kevin Scaman , Marc Lelarge

The 'Cheating Robot' version of Cops and Robbers is played on a finite, simple, connected graph. The players move in the same time period. However, before moving, the robot observes to which vertices the cops are moving and it is fast…

Combinatorics · Mathematics 2021-03-12 Melissa A. Huggan , Richard J. Nowakowski

We introduce the bodyguard problem for graphs. This is a variation of Surrounding Cops and Robber but, in this model, a smallest possible group of bodyguards must surround the president and then maintain this protection indefinitely. We…

Combinatorics · Mathematics 2025-08-15 Nancy E. Clarke , Danny Dyer , William Kellough

We show that if a sequence of dense graphs has the property that for every fixed graph F, the density of copies of F in these graphs tends to a limit, then there is a natural ``limit object'', namely a symmetric measurable 2-variable…

Combinatorics · Mathematics 2007-05-23 Laszlo Lovasz , Balazs Szegedy

We investigate a cheating robot version of Cops and Robber, first introduced by Huggan and Nowakowski, where both the cops and the robber move simultaneously, but the robber is allowed to react to the cops' moves. For conciseness, we refer…

Combinatorics · Mathematics 2024-09-19 Nancy E. Clarke , Danny Dyer , William Kellough

Inspired by a width invariant defined on permutations by Guillemot and Marx [SODA '14], we introduce the notion of twin-width on graphs and on matrices. Proper minor-closed classes, bounded rank-width graphs, map graphs, $K_t$-free unit…

Data Structures and Algorithms · Computer Science 2021-10-26 Édouard Bonnet , Eun Jung Kim , Stéphan Thomassé , Rémi Watrigant

In this paper we analyze and model three open problems posed by Harris, Insko, Prieto-Langarica, Stoisavljevic, and Sullivan in 2020 concerning the tipsy cop and robber game on graphs. The three different scenarios we model account for…

Combinatorics · Mathematics 2021-03-01 Viktoriya Bardenova , Vincent Ciarcia , Erik Insko

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

In many variants of the game of Cops and Robbers on graphs, multiple cops play against a single robber. In 2019, Cox and Sanaei introduced a variant of the game that gives the robber a more active role than simply evading the cop. In their…

Combinatorics · Mathematics 2022-05-17 Joshua Carlson , Meghan Halloran , Carolyn Reinhart

Clique-width is a well-studied graph parameter owing to its use in understanding algorithmic tractability: if the clique-width of a graph class ${\cal G}$ is bounded by a constant, a wide range of problems that are NP-complete in general…

Combinatorics · Mathematics 2021-12-23 Konrad K. Dabrowski , Matthew Johnson , Daniël Paulusma

We study topological and geometric functionals of $l_\infty$-random geometric graphs on the high-dimensional torus in a sparse regime, where the expected number of neighbors decays exponentially in the dimension. More precisely, we…

Probability · Mathematics 2025-01-08 Gilles Bonnet , Christian Hirsch , Daniel Rosen , Daniel Willhalm

The mim-width of a graph is a powerful structural parameter that, when bounded by a constant, allows several hard problems to be polynomial-time solvable - with a recent meta-theorem encompassing a large class of problems [SODA2023]. Since…

Discrete Mathematics · Computer Science 2025-12-09 Max Dupré la Tour , Manuel Lafond , Ndiamé Ndiaye

It is known that a number of natural graph problems which are FPT parameterized by treewidth become W-hard when parameterized by clique-width. It is therefore desirable to find a different structural graph parameter which is as general as…

Data Structures and Algorithms · Computer Science 2013-08-15 Jakub Gajarský , Michael Lampis , Sebastian Ordyniak

For any graph $F$ and any integer $r\geq 2$, the \emph{online vertex-Ramsey density of $F$ and $r$}, denoted $m^*(F,r)$, is a parameter defined via a deterministic two-player Ramsey-type game (Painter vs.\ Builder). This parameter was…

Combinatorics · Mathematics 2018-02-16 Torsten Mütze , Reto Spöhel

In this paper, we study the game of cops and robber on the class of graphs with no even hole (induced cycle of even length) and claw (a star with three leaves). The cop number of a graph $G$ is defined as the minimum number of cops needed…

Combinatorics · Mathematics 2022-01-12 Ramin Javadi , Ali Momeni

In this work we take a step towards characterising strongly flip-flat classes of graphs. Strong flip-flatness appears to be the analogue of uniform almost-wideness in the setting of dense classes of graphs. We prove that strongly flip-flat…

Discrete Mathematics · Computer Science 2025-12-05 Fatemeh Ghasemi , Julien Grange , Mamadou Moustapha Kanté , Florent Madelaine

Connections between structural graph theory and finite model theory recently gained a lot of attention. In this setting, many interesting questions remain on the properties of dependent (NIP) hereditary classes of graphs, in particular…

Combinatorics · Mathematics 2026-01-01 Hector Buffière , Patrice Ossona de Mendez