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arXiv · 1902.10344

Non-Hamiltonian 3-Regular Graphs with Arbitrary Girth

Michael Haythorpe
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Abstract

It is well known that 3--regular graphs with arbitrarily large girth exist. Three constructions are given that use the former to produce non-Hamiltonian 3--regular graphs without reducing the girth, thereby proving that such graphs with arbitrarily large girth also exist. The resulting graphs can be 1--, 2-- or 3--edge-connected depending on the construction chosen. From the constructions arise (naive) upper bounds on the size of the smallest non-Hamiltonian 3--regular graphs with particular girth. Several examples are given of the smallest such graphs for various choices of girth and connectedness.

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Michael Haythorpe. 2019-02-27. Non-Hamiltonian 3-Regular Graphs with Arbitrary Girth. https://arxiv.org/abs/1902.10344

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