Partial Sums of Certain Classes of Analytic Functions Defined by Generalized Differential Operator

In this paper, we introduce the class ∑^p,n,u_ λ,n of analytic functions in the open unit disc U = {z E C : |z| 1} defined by differential operator. The main aim of the present paper is to determine coefficient estimates and some results concerning the partial sums for functions f (z) belonging to this class.