Non-negative cd-coefficients of Gorensteinast posets
نویسنده
چکیده
We give a convolution formula for cd-index coefficients. The convolution formula, together with the proof by Davis and Okun of the CharneyDavis Conjecture in dimension 3, imply that certain cd-coefficients are nonnegative for all Gorenstein* posets. Additional coefficients are shown to be non-negative by interpreting them in terms of the top homology of certain Cohen-Macaulay complexes. In particular we verify, up to rank 6, Stanley’s conjecture that the coefficients in the cd-index of a Gorenstein* ranked poset are non-negative.
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عنوان ژورنال:
- Discrete Mathematics
دوره 274 شماره
صفحات -
تاریخ انتشار 2004