题目：Eulerian polynomials and excedance statistics
报告人：曾江 (法国里昂大学)
时间：8月17日，10:30-11:30
地点：明德楼B区201学术报告厅
摘要：A formula of Stembridge states that the permutation peak polynomials and descent polynomials are connected via a quadratique transformation. Rephrasing the latter formula with permutation cycle peaks and excedances we are able to prove a series of general formulas expressing polynomials counting permutations by various excedance statistics in terms of refined Eulerian polynomials. Our methods include permutation enumeration techniques involving variations of classical bijections from permutations to Laguerre histories, explicit continued fraction expansions of combinatorial generating functions. This talk is based on joint work with Bin HAN and Jianxi MAO.
