The Number of Spanning Trees in Kn-complements of Quasi-threshold Graphs

نویسندگان

  • Stavros D. Nikolopoulos
  • Charis Papadopoulos
چکیده

In this paper we examine the classes of graphs whose Kn-complements are trees or quasi-threshold graphs and derive formulas for their number of spanning trees; for a subgraph H of Kn, the Kn-complement of H is the graph Kn H which is obtained from Kn by removing the edges of H . Our proofs are based on the complement spanning-tree matrix theorem, which expresses the number of spanning trees of a graph as a function of the determinant of a matrix that can be easily constructed from the adjacency relation of the graph. Our results generalize previous results and extend the family of graphs of the form Kn H admitting formulas for the number of their spanning trees.

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عنوان ژورنال:
  • Graphs and Combinatorics

دوره 20  شماره 

صفحات  -

تاریخ انتشار 2004