Euler flag enumeration of Whitney stratified spaces
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چکیده
The idea of enumeration using the Euler characteristic was suggested throughout Rota’s work and influenced by Schanuel’s categorical viewpoint [33, 40, 41, 42]. In order to carry out such a program that is topologically meaningful and which captures the broadest possible classes of examples, two key insights are required. First, the notion of grading in the face lattice of a polytope must be relaxed. Secondly, the usual zeta function in the incidence algebra must be extended to include the Euler characteristic as an important instance.
منابع مشابه
Euler Enumeration and Beyond
This paper surveys recent results for flag enumeration of polytopes, Bruhat graphs, balanced digraphs, Whitney stratified spaces and quasi-graded posets.
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تاریخ انتشار 2012