Extension Operators Preserving Janowski Classes of Univalent Functions

Classes of admissible functions associated with certain integral operators applied to meromorphic functions

‎In the present paper‎, ‎by making use of the differential subordination and‎ ‎superordination results of Miller and Mocanu‎, ‎  ‎certain classes of admissible functions ‎are determined so that subordination as well as superordination implications‎ ‎of functions associated with an integral operator hold‎. ‎Additionally‎, ‎differential sandwich-type result is obtained‎.

Convolutions for special classes of harmonic univalent functions

Ruscheweyh‘and She&Small proved the P6lya-Schoenberg conjecture that the class of convex analytic functions is closed under convolution or Hadamard product. They also showed that clos&o-convexity is preserved under convolution with convex analytic functions. In this note, we investigate harmonic analogs. Beginning with convex analytic functions, we form certain harmonic functions which preserve...

Coefficient Estimates for Certain Classes of Bi-Univalent Functions

In this paper we introduce some new subclasses of the class σ of bi-univalent functions and obtain bounds for the initial coefficients of the Taylor series expansion of functions from the considered classes.

Coefficient Inequalities for Certain Classes of Analytic and Univalent Functions

For functions f(z) which are starlike of order α, convex of order α, and λ-spirallike of order α in the open unit disk U, some interesting sufficient conditions involving coefficient inequalities for f(z) are discussed. Several (known or new) special cases and consequences of these coefficient inequalities are also considered.

On Janowski Starlike Functions