SUBDIVISION OF COMPLEXES OF k-TREES
نویسنده
چکیده
Let Π (k) (n−1)k+1 be the poset of partitions of {1, 2, . . . , (n − 1)k + 1} with block sizes congruent to 1 modulo k. We prove that the order complex ∆(Π (k) (n−1)k+1 ) is a subdivision of the complex of k-trees T k n , thereby answering a question posed by Feichtner [F, 5.2]. The result is obtained by an ad-hoc generalization of concepts from the theory of nested set complexes to non-lattices.
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تاریخ انتشار 2005