Speaker: Ron Adin (Bar-Ilan University)

Title: "Super Mahonians"

Abstract:
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MacMahon has shown, about a hundred years ago, that the generating function 
for major index over the symmetric group has a simple product formula.
Gessel and Simion have shown that the generating function for major index 
together with sign has a similar simple factorial-type product formula. 
We give extensions of this result (including other parameters), as well as
analogues for the Weyl group of type B.

A corresponding elegant result for descent number (``super Eulerian 
distribution'') has been conjectured by Loday (1989) and proved by 
D\'esarmenien and Foata and, independently, by Wachs. A type B analogue 
was provided by Reiner.

(Joint work with Ira Gessel and Yuval Roichman)