Rong Ma,
Yuan Yi,
Yulong Zhang
(2010)
Let be an integer, let denote a Dirichlet character modulo For any real number we define the generalized Dirichlet -functions
where with and both real. They can be extended to all by analytic continuation. In this paper we study the mean value properties of the generalized Dirichlet -functions especially for and , and obtain two sharp asymptotic formulas by using the analytic method and the theory of van der Corput.