On a class of q-valent meromorphic functions with positive coefficients

摘要

In this paper we introduce a new subclass S* (α,β,ξ,ν) consisting of functions f(z) =1/Zq+∑∞/(n=0)aq+nZq+n,(aq+n ≥0,q ∈N)which are analytic and q-valent in the punctured unit disc E = {z : 0 ＜|z|＜1} with multiple pole at z = 0. Some results like coefficient estimates, growth and distortion theorem, extreme points, convolution theorem and other interesting properties are investigated. The results investigated here are shown to be sharp.