Abstract

We introduce a class of univalent functions Rn(λ,α) defined by a new differential operator Dnf(z), n0={0,1,2,}, where D0f(z)=f(z), D1f(z)=(1λ)f(z)+λzf(z)=Dλf(z), λ0, and Dnf(z)=Dλ(Dn1f(z)). Inclusion relations, extreme points of Rn(λ,α), some convolution properties of functions belonging to Rn(λ,α), and other results are given.