On non-Hamiltonian circulant digraphs of outdegree three
نویسندگان
چکیده
We construct infinitely many connected, circulant digraphs of outdegree three that have no hamiltonian circuit. All of our examples have an even number of vertices, and our examples are of two types: either every vertex in the digraph is adjacent to two diametrically opposite vertices, or every vertex is adjacent to the vertex diametrically opposite to itself.
منابع مشابه
Hamiltonian cycles in (2, 3, c)-circulant digraphs
Let D be the circulant digraph with n vertices and connection set {2, 3, c}. (Assume D is loopless and has outdegree 3.) Work of S.C. Locke and D.Witte implies that if n is a multiple of 6, c ∈ {(n/2) + 2, (n/2) + 3}, and c is even, then D does not have a hamiltonian cycle. For all other cases, we construct a hamiltonian cycle in D.
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ورودعنوان ژورنال:
- Journal of Graph Theory
دوره 30 شماره
صفحات -
تاریخ انتشار 1999