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Related papers: Cops and robbers on $P_5$-free graphs

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This paper considers the Cops and Attacking Robbers game, a variant of Cops and Robbers, where the robber is empowered to attack a cop in the same way a cop can capture the robber. In a graph $G$, the number of cops required to capture a…

Combinatorics · Mathematics 2024-08-06 Alexander Clow , Melissa A. Huggan , M. E. Messinger

Cops and Robbers is a well-studied pursuit-evasion game in which a set of cops seeks to catch a robber in a graph G, where cops and robber move along edges of G. The cop number of G is the minimum number of cops that is sufficient to catch…

We generalise the popular cops and robbers game to multi-layer graphs, where each cop and the robber are restricted to a single layer (or set of edges). We show that initial intuition about the best way to allocate cops to layers is not…

Combinatorics · Mathematics 2026-02-10 Jessica Enright , Kitty Meeks , William Pettersson , John Sylvester

The cop number of a graph $G$ is the smallest $k$ such that $k$ cops win the game of cops and robber on $G$. We investigate the maximum cop number of geometric intersection graphs, which are graphs whose vertices are represented by…

In the game of Cops and Robbers, one of the most useful results is that an isometric path in a graph can be guarded by one cop. In this paper, we introduce the concept of wide shadow in a subgraph, and use it to characterize all 1-guardable…

Combinatorics · Mathematics 2024-06-04 Sebastián González Hermosillo de la Maza , Bojan Mohar

We consider a game in which a cop searches for a moving robber on a connected graph using distance probes, which is a slight variation on one introduced by Seager. Carragher, Choi, Delcourt, Erickson and West showed that for any $n$-vertex…

Combinatorics · Mathematics 2017-11-23 John Haslegrave , Richard A. B. Johnson , Sebastian Koch

Andreae (1986) proved that the cop number of connected $H$-minor-free graphs is bounded for every graph $H$. In particular, the cop number is at most $|E(H-h)|$ if $H-h$ contains no isolated vertex, where $h\in V(H)$. The main result of…

Combinatorics · Mathematics 2025-10-29 Franklin Kenter , Erin Meger , Jérémie Turcotte

Various models to quantify the reliability of a network have been studied where certain components of the graph may fail at random and the probability that the remaining graph is connected is the proxy for reliability. In this work we…

Combinatorics · Mathematics 2020-11-24 Maimoonah Ahmed , Ben Cameron

Cops and Robber is a well-studied two-player pursuit-evasion game played on a graph, where a group of cops tries to capture the robber. The \emph{cop number} of a graph is the minimum number of cops required to capture the robber.…

Discrete Mathematics · Computer Science 2025-04-11 Sandip Das , Harmender Gahlawat

In this short paper we study the game of cops and robbers, which is played on the vertices of some fixed graph $G$. Cops and a robber are allowed to move along the edges of $G$ and the goal of cops is to capture the robber. The cop number…

Combinatorics · Mathematics 2010-04-13 Alex Scott , Benny Sudakov

We consider the well-studied cops and robbers game in the context of oriented graphs, which has received surprisingly little attention to date. We examine the relationship between the cop numbers of an oriented graph and its underlying…

Cops and Robbers is a type of pursuit-evasion game played on a graph where a set of cops try to capture a single robber. The cops first choose their initial vertex positions, and later the robber chooses a vertex. The cops and robbers make…

Discrete Mathematics · Computer Science 2024-09-25 Prosenjit Bose , Jean-Lou De Carufel , Anil Maheshwari , Karthik Murali

In this paper, we prove that for every connected graph G, there exists a split graph H with the same independence number and the same order. Then we propose a first algorithm for finding this graph, given the degree sequence of the input…

Discrete Mathematics · Computer Science 2008-01-09 Omar Kettani

The game of cops and robbers is a pursuit game on graphs where a set of agents, called the cops try to get to the same position of another agent, called the robber. Cops and robbers has been studies on several classes of graphs including…

Combinatorics · Mathematics 2019-03-19 Seyyed Aliasghar Hosseini , Masood Masjoody , Ladislav Stacho

A hole in a graph is an induced cycle of length at least 4. We give a simple winning strategy for t-3 cops to capture a robber in the game of cops and robbers played in a graph that does not contain a hole of length at least t. This…

Combinatorics · Mathematics 2020-01-03 Vaidy Sivaraman

We prove new theoretical results about several variations of the cop and robber game on graphs. First, we consider a variation of the cop and robber game which is more symmetric called the cop and killer game. We prove for all $c < 1$ that…

Discrete Mathematics · Computer Science 2017-11-01 Espen Slettnes , Carl Joshua Quines , Shen-Fu Tsai , Jesse Geneson

In this short paper we study the game of Cops and Robbers, played on the vertices of some fixed graph $G$ of order $n$. The minimum number of cops required to capture a robber is called the cop number of $G$. We show that the cop number of…

Combinatorics · Mathematics 2014-09-30 Zsolt Adam Wagner

Meyniel's conjecture states that $n$-vertex connected graphs have cop number $O(\sqrt{n})$. The current best known upper bound is $n/2^{(1-o(1))\sqrt{\log n}}$, proved independently by Lu and Peng (2011), and by Scott and Sudakov (2011). In…

Combinatorics · Mathematics 2026-02-10 Prosenjit Bose , Louis Esperet , Jędrzej Hodor , Gwenaël Joret , Piotr Micek , Clément Rambaud

In the ordinary version of the pursuit-evasion game "cops and robbers", a team of cops and a robber occupy vertices of a graph and alternately move along the graph's edges, with perfect information about each other. If a cop lands on the…

Combinatorics · Mathematics 2016-06-29 Brendan W. Sullivan , Nikolas Townsend , Mikayla Werzanski

The game of \emph{Cops and Robber} is usually played on a graph, where a group of cops attempt to catch a robber moving along the edges of the graph. The \emph{cop number} of a graph is the minimum number of cops required to win the game.…

Combinatorics · Mathematics 2024-04-29 Joshua Erde , Mihyun Kang , Florian Lehner , Bojan Mohar , Dominik Schmid