MIT Combinatorics Seminar

Relations among ribbon Schur functions

Louis Billera  (Cornell University)

Monday, November 29, 2004    4:15 pm    Room 2-338


Note that this talk will be on Monday!

Ribbon Schur functions are skew Schur functions corresponding to "ribbon" or "border strip" Ferrers shapes, namely, connected diagrams with no 2 x 2 squares. Those with n boxes naturally correspond to integer compositions of n. We give necessary and sufficient conditions for two such compositions to give identical Schur functions. This involves a notion of combining compositions that corresponds to computing descent sets in tensor products of permutations.