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Graph powers and k-ordered Hamiltonicity

Denis Chebikin
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Abstract

It is known that if G is a connected simple graph, then G^3 is Hamiltonian (in fact, Hamilton-connected). A simple graph is k-ordered Hamiltonian if for any sequence v_1, v_2, ..., v_k of k vertices there is a Hamiltonian cycle containing these vertices in the given order. In this paper, we prove that G^(3k/2 + 1) is k-ordered Hamiltonian for a connected graph G on at least k vertices. We further show that if G is connected, then G^4 is 4-ordered Hamiltonian and that if G is Hamiltonian, then G^3 is 5-ordered Hamiltonian. We also give bounds on the smallest power p_k such that G^p_k is k-ordered Hamiltonian for G=P_n and G=C_n.

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Denis Chebikin. 2003-07-28. Graph powers and k-ordered Hamiltonicity. https://arxiv.org/abs/math/0307359

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