Graphs and digraphs with all 2-factors isomorphic
نویسندگان
چکیده
We show that a digraph which contains a directed 2-factor and has minimum in-degree and out-degree at least four has two non-isomorphic directed 2-factors. As a corollary we deduce that every graph which contains a 2factor and has minimum degree at least eight has two non-isomorphic 2factors. In addition we construct: an infinite family of strongly connected 3-diregular digraphs with the property that all their directed 2-factors are isomorphic, an infinite family of 2-connected 4-regular graphs with the property that all their 2-factors are isomorphic, and an infinite family of cyclically 6-edge-connected cubic graphs with the property that all their 2-factors are hamiltonian cycles.
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عنوان ژورنال:
- J. Comb. Theory, Ser. B
دوره 92 شماره
صفحات -
تاریخ انتشار 2004