A New Index for Polytopes
نویسندگان
چکیده
A new index for convex polytopes is introduced. It is a vector whose length is the dimension of the linear span of the flag vectors of polytopes. The existence of this index is equivalent to the generalized Dehn-Sommerville equations. It can be computed via a shelling of the polytope. The ranks of the middle perversity intersection homology of the associated toric variety are computed from the index. This gives a proof of a result of Kalai on the relationship between the Betti numbers of a polytope and those of its dual.
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عنوان ژورنال:
- Discrete & Computational Geometry
دوره 6 شماره
صفحات -
تاریخ انتشار 1991