Statistics on permutations with bounded drop size

Abstract

Permutations with bounded drop size, which we also call bounded permutations, was introduced by Chung, Claesson, Dukes and Graham. Petersen introduced a new Mahonian statistic the sorting index, which is denoted by $\sor$. Meanwhile, Wilson introduced the statistic $\DIS$, which turns out to satisfy that $\sor(\sigma)=\DIS(\sigma^{-1})$ for any permutation $\sigma$. In this paper, we maintain Petersen's method to deduce the generating functions of $(\inv, \lmax)$ and $(\DIS, \cyc)$ over bounded permutations to show their equidistribution. Moreover, the generating function of $\des$ over $213$-avoiding bounded permutations and some related equidistributions are given as well.