 The corresponding principal series representation is denoted "I"ε,μ.It turns out that ε is the central character of the induced representation and the complex number μ may be identified with the infinitesimal character via the Harish-Chandra isomorphism.The principal series representation "I"ε,μ (or more precisely its Harish-Chandra module of "K"-finite elements) admits a basis consisting of elements "w""j", where the index "j" runs through the even integers if ε=1 and the odd integers if ε=-1.