报告人：曾江教授（法国里昂大学）
时间：11月1日 10：30-11：30
地点：数学楼301
报告摘要: The Euler numbers are the coeffcients in the Taylor expansion of tan x+sec x.
A classical result of Andre says that these coecents enumerate alternating permutations. In the 1970's Foata and Shcutzenberger found another family of permutations called Andre permutations, also enumerated by Euler numbers and proved that the descent polynomials of Andre permutations are related to the gamma-coefficients of Eulerian polynomials. In this talk, I will present a (p; q)-analogue of their result using the combinatorial theory of continued fractions, which gives a satisfactory answer to a conjecture of Branden on the gamma-coefficients of his (p; q)-analogue of Eulerian polynomials. In particular, we answer a recent question of G.N. Han on his q-Euler numbers.
报告人简介：曾江教授是法国里昂大学教授，研究方向为组合学，特殊函数和数论