Inequalities for cd-indices of joins and products of polytopes

被引：11

作者：

Ehrenborg, R ^{[1
]}

Fox, H

机构：

[1] Univ Kentucky, Dept Math, Lexington, KY 40506 USA

[2] MIT, Artificial Intelligence Lab, Cambridge, MA 02139 USA

来源：

COMBINATORICA | 2003年 / 23卷 / 03期

基金：

美国国家科学基金会;

关键词：

D O I：

10.1007/s00493-003-0026-z

中图分类号：

O1 [数学];

学科分类号：

0701 ; 070101 ;

摘要：

The cd-index is a polynomial which encodes the flag f-vector of a convex polytope. For polytopes U and V, we determine explicit recurrences for computing the cd-index of the free join UOV and the cd-index of the Cartesian product UxV. As an application of these recurrences, we prove the inequality Psi(UO(VxW))less-than-or-equal-to Psi((UOV)xW) involving the cd-indices of three polytopes.

引用

收藏

页码：427 / 452

页数：26

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