Complexes of Directed Trees of Complete Multipartite Graphs
نویسنده
چکیده
For every directed graph D we consider the complex of all directed subforests Δ(D). The investigation of these complexes was started by D. Kozlov. We generalize a result of Kozlov and prove that complexes of directed trees of complete multipartite graphs are shellable. We determine the h-vector of Δ(Km,n) and the homotopy type of Δ( −→ Kn1,n2,...,nk ).
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تاریخ انتشار 2012