============================== Bar-Ilan Combinatorics Seminar ============================== The last meeting of the seminar this year will take place, IYH, on (when) Tuesday, 1 Tamuz (June 23) 12:00-13:30 (where) Room 201 (Math Dept Seminar Room), Math and CS Building (216), Bar-Ilan University (who) Moti Novick (Hebrew University) will talk about (what) "The equidistribution of Inversion Number and Major Index over S_n: A new bijective proof" Abstract: We present a bijective proof, different from Foata's 1968 proof, of MacMahon's 1916 result concerning the equidistribution of the inversion number and major index over all permutations of {1,2,...,n}. We generalize this to a proof of a theorem of Garsia and Gessel from 1979 which provides a generating function for the major index over shuffles of ordered complementary subsets of {1,2,...,n}. Special cases of this theorem include MacMahon's result and also the 1978 result of Foata and Schutzenberger proving the equidistribution of these two statistics over inverse descent classes. Our method provides a bijective proof of the latter equidistribution result as well. ************************************************************************* You are all invited ! (Graduate students especially welcome) If you want to give a talk at the seminar, or know a prospective speaker, please contact Ron Adin . Seminar's homepage: *************************************************************************