Bruhat Order on Partial Fixed Point Free Involutions
نویسندگان
چکیده
Our purpose in this article is to investigate the order complex of inclusion poset PFn of Borel orbit closures in skew-symmetric matrices. We prove that PFn is an EL-shellable poset and furthermore its order complex triangulates a ball. We investigate (rook-theoretic) combinatorial properties of the rank-generating function of PFn in contrast with the zeta function of the variety of skew-symmetric matrices over finite fields.
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عنوان ژورنال:
- Electr. J. Comb.
دوره 21 شماره
صفحات -
تاریخ انتشار 2014