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arXiv · 2502.19724

On weak cop numbers of transitive graphs

Florian Lehner
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Abstract

The weak cop number of infinite graphs can be seen as a coarse-geometric analogue to the cop number of finite graphs. We show that every vertex transitive graph with at least one thick end has infinite weak cop number. It follows that every connected, vertex transitive graph has weak cop number $1$ or $\infty$, answering a question posed by Lee, Martínez-Pedroza, and Rodríguez-Quinche, and reiterated in recent preprints by Appenzeller and Klinge, and by Esperet, Gahlawat, and Giocanti.

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Florian Lehner. 2025-03-13. On weak cop numbers of transitive graphs. https://arxiv.org/abs/2502.19724

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