Abstract
We count derangements, involutions and unimodal elements in the wreath product C r ≀ S n by the numbers of excedances, fixed points and 2-cycles. Properties of the generating functions, including combinatorial formulas, recurrence relations and real-rootedness are studied. The results obtained specialize to those on the symmetric group S n and on the hyperoctahedral group B n when r = 1, 2, respectively.
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Chow, CO., Mansour, T. Counting derangements, involutions and unimodal elements in the wreath product C r ≀ S n . Isr. J. Math. 179, 425–448 (2010). https://doi.org/10.1007/s11856-010-0088-8
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DOI: https://doi.org/10.1007/s11856-010-0088-8