On certain meromorphic p-valent starlike functions

摘要

A certain differential operator D~(n+p) is introduced for functions of the formrnf(z) = 1/z~p + a_0/z~(p-1) + … + a_(k + p - 1)z~k + …rnwhich are regular in the annulus E~* = {z ∈ C : 0 < |z| < 1}, where p is a positive integer. The main object of this paper is to give an application of the operator D~(n+p) to the differential inequalities.