%0 Journal Article %T Arithmetic of character varieties of free groups %A Sergey Mozgovoy %A Markus Reineke %J Mathematics %D 2014 %I arXiv %X Via counting over finite fields, we derive explicit formulas for the E-polynomials and Euler characteristics of GL(d)- and PGL(d)-character varieties of free groups. We prove a positivity property for these polynomials and relate them to the number of subgroups of finite index. %U http://arxiv.org/abs/1402.6923v1