Products of polytopes and inequalities
نویسنده
چکیده
The cd-index is a polynomial which encodes the ag f-vector of a convex polytope. We determine explicit recurrences for computing the cd-index of the free join U _ V of two polytopes U and V and the cd-index of the Cartesian product U V. As an application of these recurrences, we prove the inequality (U _ (V W)) ((U _ V) W) involving the cd-indices of three polytopes.
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تاریخ انتشار 1999