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arXiv · 2602.14388

Hamilton Cycles in Semisymmetric Graphs

Shaofei Du·Kai Yuan
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Abstract

In light of Lov\'{a}sz's longstanding question on the existence of Hamilton paths in vertex-transitive graphs, this paper considers a natural variant: what if vertex-transitivity is relaxed, yet a high degree of symmetry--specifically edge-transitivity--is retained? To investigate this, we focus on the class of semisymmetric graphs, which are regular, edge-transitive, but not vertex-transitive. In this paper, it will be shown that every connected semisymmetric graph of order $2pq$, where $p$ and $q$ are two distinct primes contains a Hamilton cycle and that every connected cubic semisymmetric graph of order less than 3000 contains a Hamilton cycle too. Based on these observations, the following question is posed: construct a connected semisymmetric graph which has no Hamilton cycle.

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Shaofei Du, Kai Yuan. 2026-02-16. Hamilton Cycles in Semisymmetric Graphs. https://arxiv.org/abs/2602.14388

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