a Department of Mathematics & Statistics, Loyola University Chicago, Chicago, IL 60660, United States b Department of Mathematics, Wake Forest University, Winston-Salem, NC 27109, United States
Abstract:
We prove that the subset of quasisymmetric polynomials conjectured by Bergeron and Reutenauer to be a basis for the coinvariant space of quasisymmetric polynomials is indeed a basis. This provides the first constructive proof of the Garsia-Wallach result stating that quasisymmetric polynomials form a free module over symmetric polynomials and that the dimension of this module is n!.