The additive divisor problem and its analogs for Fourier coefficients of cusp forms. I.
Let be the nth normalized Fourier coefficient of a holomorphic Hecke eigenform . We establish that for j = 2,3,4, which improves the previous results. For j = 2, we even establish a better result.
Let be a nonzero cuspidal Hecke eigenform of weight and the trivial nebentypus , where the Fourier coefficients are real. Bruinier and Kohnen conjectured that the signs of are equidistributed. This conjecture was proved to be true by Inam, Wiese and Arias-de-Reyna for the subfamilies , where is a squarefree integer such that . Let and be natural numbers such that . In this work, we show that is equidistributed over any arithmetic progression .
In this paper we derive, using the Gauss summation theorem for hypergeometric series, a simple integral expression for the reciprocal of Euler’s beta function. This expression is similar in form to several well-known integrals for the beta function itself.We then apply our new formula to the study of Whittaker functions, which are special functions that arise in the Fourier theory for automorphic forms on the general linear group. Specifically, we deduce explicit integral representations of “fundamental”...