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arXiv · 2208.06189

Cubic vertex-transitive graphs admitting automorphisms of large order

Primož Potočnik·Micael Toledo
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Abstract

A connected graph of order $n$ admitting a semiregular automorphism of order $n/k$ is called a $k$-multicirculant. Highly symmetric multicirculants of small valency have been extensively studied, and several classification results exist for cubic vertex- and arc-transitive multicirculants. In this paper we study the broader class of cubic vertex-transitive graphs of order $n$ admitting an automorphism of order $n/3$ or larger that may not be semiregular. In particular, we show that any such graph is either a $k$-multicirculant for some $k \leq 3$, or it belongs to an infinite family of graphs of girth $6$.

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Primož Potočnik, Micael Toledo. 2022-08-12. Cubic vertex-transitive graphs admitting automorphisms of large order. https://arxiv.org/abs/2208.06189

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