The Euler characteristic of a Hecke algebra

T. Terragni, Th. Weigel

Published 2011-10-22, updated 2014-05-23Version 4

It is shown that the Euler characteristic $\chi_{(\mathcal{H},\mathcal{B},\epsilon_q)}$ of a $\mathbb{Z}[[q]]$-Hecke algebra $\mathcal{H}$ associated with a finitely generated Coxeter group $(W,S)$ coincides with $p_{(W,S)}(q)^{-1}$, where $p_{(W,S)}(t)$ is the Poincar\'e series of $(W,S)$.