A result of Foata and Schützenberger states that two statistics on permutations, the number of inversions and the inverse major index, have the same distribution on a descent class. We give a multivariate generalization of this property: the sorted vectors of the Lehmer code, of the inverse majcode, and of a new code (the inverse saillance code), have the same distribution on a descent class, and their common multivariate generating function is a flagged ribbon Schur function.
Riccardo Biagioli, 2008, Equidistribution of negative statistics and quotients of Coxeter groups of type B and D, arXiv (Cornell University), 41, 3, pp. 378-394, 10.1016/j.aam.2008.03.001, https://arxiv.org/abs/0707.2741.