The cd -index of fans and posets
نویسنده
چکیده
The number of flags in a complete fan, or more generally in an Eulerian poset, is encoded in the cd-index. We prove the non-negativity of the cd-index for complete fans, regular CW -spheres and Gorenstein* posets.
منابع مشابه
SIGNS IN THE cd-INDEX OF EULERIAN PARTIALLY ORDERED SETS
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تاریخ انتشار 2006