Excedances of affine permutations
نویسندگان
چکیده
We introduce an excedance statistic for the group of affine permutations S̃n and determine the generating function of its distribution. The proof involves working with enumerating lattice points in a skew version of the root polytope of type A. We also show that the left coset representatives of the quotient S̃n/Sn correspond to increasing juggling sequences and determine their Poincaré series.
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