A proof of Björner’s totally nonnegative conjecture
نویسندگان
چکیده
The McMullen Correspondence gives a linear dependence between Msequences of length ⌊ d 2 ⌋+1 and f–vectors of simplical d–polytopes. Denote the transfer matrix between g and f by Md. Recently, Björner proved that any 2×2–minor of Md is nonnegative and conjectured that the same would be true for arbitrary minors. In this paper we answer the question in the affirmative.
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تاریخ انتشار 2008