Enumeration of Difference Graphs
نویسندگان
چکیده
A difference graph is a bipartite graph G = (X, Y: E) such that all the neighborhoods of the vertices of X are comparable by inclusion. We enumerate labeled and unlabeled difference graphs with or without a bipartition of the vertices into two stable sets. The labeled enumerations are expressed in terms of combinatorial numbers related to the Stirling numbers of the second kind.
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ورودعنوان ژورنال:
- Discrete Applied Mathematics
دوره 60 شماره
صفحات -
تاریخ انتشار 1995