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arXiv · 2006.02998

4-cop-win graphs have at least 19 vertices

Jérémie Turcotte·Samuel Yvon
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Abstract

We show that the cop number of any graph on 18 or fewer vertices is at most 3. This answers a question posed by Andreae in 1986, as well as more recently by Baird et al. We also find all 3-cop-win graphs on 11 vertices, narrow down the possible 4-cop-win graphs on 19 vertices and make some progress on finding the minimum order of 3-cop-win planar graphs.

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Jérémie Turcotte, Samuel Yvon. 2021-05-12. 4-cop-win graphs have at least 19 vertices. https://doi.org/10.1016/j.dam.2021.05.012

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