Parity Theorems for Statistics on Permutations and Catalan Words
نویسنده
چکیده
We establish parity theorems for statistics on the symmetric group Sn, the derangements Dn, and the Catalan words Cn, giving both algebraic and bijective proofs. For the former, we evaluate q-generating functions at q = −1; for the latter, we define appropriate signreversing involutions. Most of the statistics involve counting inversions or finding the major index of various words.
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تاریخ انتشار 2005