A note on the number of coefficients of automorphic functions for with same signs
arXiv:1405.0643
Abstract
Let be an irreducible unitary cuspidal representation of and be the global function attached to . If , has a Dirichlet series expression. When is self-contragradient, all the coefficients of Dirichlet series are real. In this note, we shall give non-trivial lower bounds for the number of positive and negative coefficients respectively, which is an improvement on the recent work of Jianya Liu and Jie Wu.