André permutations, lexicographic shellability and the $cd$-index of a convex polytope
نویسندگان
چکیده
منابع مشابه
Lexicographic shellability of partial involutions
In this manuscript we study inclusion posets of Borel orbit closures on (symmetric) matrices. In particular, we show that the Bruhat poset of partial involutions is a lexicographically shellable poset. We determine which subintervals of the Bruhat posets are Eulerian, and moreover, by studying certain embeddings of the symmetric groups and their involutions into rook matrices and partial involu...
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ژورنال
عنوان ژورنال: Transactions of the American Mathematical Society
سال: 1993
ISSN: 0002-9947,1088-6850
DOI: 10.1090/s0002-9947-1993-1094560-9