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Related papers: A study of cops and robbers in oriented graphs

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An oriented graph is a directed graph without any cycle of length at most 2. To push a vertex of a directed graph is to reverse the orientation of the arcs incident to that vertex. Klostermeyer and MacGillivray defined push graphs which are…

Discrete Mathematics · Computer Science 2015-08-31 Sagnik Sen

We study the game of Cops and Robbers, where cops try to capture a robber on the vertices of a graph. Meyniel's conjecture states that for every connected graph $G$ on $n$ vertices, the cop number of $G$ is upper bounded by $O(\sqrt{n})$,…

Combinatorics · Mathematics 2019-09-09 Fatemeh Hasiri , Igor Shinkar

We provide a game theoretic framework for the game of cops and robbers (CR). Within this framework we study certain assumptions which underlie the concepts of optimal strategies and capture time. We also point out a connection of these…

Discrete Mathematics · Computer Science 2014-07-08 Athanasios Kehagias , Georgios Konstantinidis

A (finite or infinite) graph is called constructible if it may be obtained recursively from the one-point graph by repeatedly adding dominated vertices. In the finite case, the constructible graphs are precisely the cop-win graphs, but for…

Combinatorics · Mathematics 2022-08-02 Maria-Romina Ivan , Imre Leader , Mark Walters

We investigate the asymptotic number of induced subgraphs in power-law uniform random graphs. We show that these induced subgraphs appear typically on vertices with specific degrees, which are found by solving an optimization problem.…

Combinatorics · Mathematics 2022-02-23 Clara Stegehuis

Bandits with feedback graphs are powerful online learning models that interpolate between the full information and classic bandit problems, capturing many real-life applications. A recent work by Zhang et al. (2023) studies the contextual…

Machine Learning · Computer Science 2024-02-14 Mengxiao Zhang , Yuheng Zhang , Haipeng Luo , Paul Mineiro

A main question in graphical models and causal inference is whether, given a probability distribution $P$ (which is usually an underlying distribution of data), there is a graph (or graphs) to which $P$ is faithful. The main goal of this…

Statistics Theory · Mathematics 2018-01-30 Kayvan Sadeghi

An edge-colored directed graph is \emph{observable} if an agent that moves along its edges is able to determine his position in the graph after a sufficiently long observation of the edge colors. When the agent is able to determine his…

Multiagent Systems · Computer Science 2007-05-23 Raphael M. Jungers , Vincent D. Blondel

In 2019, Sivaraman conjectured that every $P_k$-free graph has cop number at most $k-3$. In the same year, Liu proved this conjecture for $(P_k,\text{claw})$-free graphs. Recently Chudnovsky, Norin, Seymour, and Turcotte proved this…

Combinatorics · Mathematics 2025-09-16 Alexander Clow , Erin Meger

An oriented graph $G^\sigma$ is a digraph without loops or multiple arcs whose underlying graph is $G$. Let $S\left(G^\sigma\right)$ be the skew-adjacency matrix of $G^\sigma$ and $\alpha(G)$ be the independence number of $G$. The rank of…

Combinatorics · Mathematics 2017-04-25 J. Huang , S. C. Li , H. Wang

Entanglement is a digraph complexity measure that origins in fixed-point theory. Its purpose is to count the nested depth of cycles in digraphs. In this paper we prove that the class of undirected graphs of entanglement at most $k$, for…

Discrete Mathematics · Computer Science 2009-04-13 Walid Belkhir

The paper focuses on two problems: (i) how to orient the edges of an undirected graph in order to maximize the number of ordered vertex pairs (x,y) such that there is a directed path from x to y, and (ii) how to orient the edges so as to…

Data Structures and Algorithms · Computer Science 2015-06-02 S. L. Hakimi , E. Schmeichel , Neal E. Young

In this paper, we investigate the ratio of the numbers of odd and even cycles in outerplanar graphs. We verify that the ratio generally diverges to infinity as the order of a graph diverges to infinity. We also give sharp estimations of the…

Combinatorics · Mathematics 2021-05-07 Akihiro Higashitani , Naoki Matsumoto

We consider generalisations of tree width to directed graphs, that attracted much attention in the last fifteen years. About their relative strength with respect to "bounded width in one measure implies bounded width in the other" many…

Discrete Mathematics · Computer Science 2014-08-21 Łukasz Kaiser , Stephan Kreutzer , Roman Rabinovich , Sebastian Siebertz

\textit{Pursuit-evasion games} have been intensively studied for several decades due to their numerous applications in artificial intelligence, robot motion planning, database theory, distributed computing, and algorithmic theory.…

Discrete Mathematics · Computer Science 2023-07-11 Harmender Gahlawat , Meirav Zehavi

The problem of finding dominators in a directed graph has many important applications, notably in global optimization of computer code. Although linear and near-linear-time algorithms exist, they use sophisticated data structures. We…

Data Structures and Algorithms · Computer Science 2013-10-09 Wojciech Fraczak , Loukas Georgiadis , Andrew Miller , Robert E. Tarjan

We show that the cop number of the Cayley sum graph of a finite group $G$ with respect to a symmetric subset $S$ is at most twice its degree when the graph is connected, undirected. We also prove that a similar bound holds for the cop…

Combinatorics · Mathematics 2025-04-29 Arindam Biswas , Jyoti Prakash Saha

This paper introduced a pursuit and evasion game to be played on a connected graph. One player moves invisibly around the graph, and the other player must guess his position. At each time step the second player guesses a vertex, winning if…

Combinatorics · Mathematics 2017-01-24 John Haslegrave

An orientation of a graph $G$ is {\it in-out-proper} if any two adjacent vertices have different in-out-degrees, where the in-out-degree of each vertex is equal to the in-degree minus the out-degree of that vertex. The {\it in-out-proper…

Combinatorics · Mathematics 2021-06-28 Ali Dehghan

A graph is an opposition graph, respectively, a coalition graph, if it admits an acyclic orientation which puts the two end-edges of every chordless 4-vertex path in opposition, respectively, in the same direction. Opposition and coalition…

Discrete Mathematics · Computer Science 2015-07-03 Van Bang Le , Thomas Podelleck
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