The genus distributions of 4-regular digraphs
نویسندگان
چکیده
An embedding of an Eulerian digraph in orientable surfaces was introduced by Bonnington et al. They gave some problems which need to be further studied. One of them is whether the embedding distribution of an embeddable digraph is always unimodal. In this paper, we first introduce the method of how to determine the faces and antifaces from a given rotation scheme of a digraph. The genus distributions of two new kinds of 4-regular digraphs in orientable surfaces are obtained. The genus distributions of one kind of digraph are strong unimodal, which gives a partial answer to the above problem. ∗ Supported by Beijing Jiaotong University fund No. 2004SM054 and NNSFC No. 10571013. Corresponding author. 80 R. HAO, Y. LIU, T. ZHANG AND L. XU
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ورودعنوان ژورنال:
- Australasian J. Combinatorics
دوره 43 شماره
صفحات -
تاریخ انتشار 2009