| The divisor functions are the basic arithmetic functions in number theory.Hence the behavior of the divisor functions are very important in the theory of automorphic L-funcions.In this thesis,we consider the oscillation behavior of the divisor function and the exponential function in arithmetic progressions.Let φ(x)be a smooth function of compact support in(0,∞)with derivatives bounded by φ(j)(x)<<1 and d3(n)be the number of ways to write n as a product of three factors.We get the asymptotic formula for the nonlinear exponential sum In this thesis,we can get two theorems.In Theorem 1,let k,l,q∈N.Then for any ?>0 and q<<X1/3-?,we have where c(φ)=∫0∞uφ(u3)du.Under the conditions of Theorem 1,let q be a prime number,and we can obtain the more precise result. |