A Note on Enumeration of One-Vertex Maps∗
نویسندگان
چکیده
The number of distinct maps with a single vertex and valence d is computed for any value of d. The question of what precisely is meant by a map can be answered in several different ways. We enumerate 16 different types of objects where each type is obtained by selecting whether the object is a pre-map or a map, is oriented or general, whether the underlying graph or pre-graph is signed or unsigned, is directed or undirected.
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تاریخ انتشار 2009