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arXiv · 2508.19880

Cubic vertex-transitive graphs of girth seven

Maruša Lekše·Micael Toledo
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Abstract

In this paper we classify cubic vertex-transitive graphs of girth $7$, based on their signature. Such a graph is either a truncation of an arc-transitive dihedral scheme on a $7$-regular graph, the skeleton of a rotary map of type $\{7,3\}$, a member of an infinite family of Cayley graphs, or is one of the of the generalised Petersen graphs $\text{Pet}(13,5)$, $\text{Pet}(15,4)$, $\text{Pet}(17,4)$ or the Coxeter graph. We show that for a cubic vertex-transitive graphs $Γ$ of girth $7$, if every edge of $Γ$ is contained in the same number of $7$-cycles, then $Γ$ is also arc-transitive.

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Maruša Lekše, Micael Toledo. 2025-08-27. Cubic vertex-transitive graphs of girth seven. https://arxiv.org/abs/2508.19880

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