Polygon Dissections and Some Generalizations of Cluster Complexes for the Classical Reflection Groups
نویسنده
چکیده
We define a simplicial complex ∆ W in terms of polygon dissections for every classical reflection group W and positive integer m. For m = 1, ∆ W is isomorphic to the cluster complex corresponding to W , defined in [8]. We enumerate the faces of ∆ W and show that the entries of its h-vector are given by the generalized Narayana numbers N W (i), defined in [3]. We also prove that for any m ≥ 1 the complex ∆ W is shellable and hence Cohen-Macaulay.
منابع مشابه
Polygon dissections and some generalizations of cluster complexes
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