A Blossoming Algorithm for Tree Volumes of Composite Digraphs
نویسنده
چکیده
A weighted composite digraph is obtained from some weighted digraph by replacing each vertex with a weighted digraph. In this paper, we give a beautiful combinatorial proof of the formula for forest volumes of composite digraphs obtained by Kelmans-Pak-Postnikov [7]. Moreover, a generalization of this formula is present.
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