2019/07/30 by Ma, Shi-Mei, Ma, Jun, Yeh, Yeong-Nan
#05A05 #05E45 #Combinatorics (math.CO) #FOS: Mathematics
paper · doi:10.48550/arxiv.1907.13082
In this paper, we study Eulerian polynomials for permutations and signed permutations of the multiset \1,1,2,2,…,n,n\. Properties of these polynomials, including recurrence relations and unimodality are discussed. In particular, we give a unified proof of the fact that these polynomials are unimodal with modes in the middle.