Subclass of univalent harmonic functions defined by dual convolution

The object of this paper is to give some applications of differential subordination concept on subclasses of univalent functions for some convolution operators which are defined on the space of univalent meromorphic functions in the punctured open unit disc. Moreover, we derive some sandwich theorems, we study some geometric properties like coefficient bounds, distortion theorem, and radii of starlikeness and convexity for these classes of functions. Extreme points and integral operator are also investigated.

In this current work, by using a relation of subordination, we define a new subclass of starlike harmonic functions. We get coefficient bounds, distortion theorems, extreme points, convolution and convex combinations for this class of functions. Moreover, some relevant connections of the results presented here with diverse known results are briefly denoted.

In the present paper, we have introduced a new subclass of analytic functions involving integral operator defined by polylogarithm function. Necessary and sufficient conditions are obtained for this class. Further distortion theorem, linear combination and results on partial sums are investigated.

In this paper, using Differential operator a certain subclass of harmonic univalent functions in the unit disc U = {z ∈ C : |z| < 1} is investigated. Some properties such as coefficient bounds, convex combination, extreme points and convolution conditions of this class are obtained. The newly introduced subclass of harmonic univalent functions is more general than the subclasses earlier found in the literature.

We investigate some properties of a new subclass of harmonic univalent functions defined by multiplier transformation. We obtain coefficient conditions, extreme points, distortion bounds, convolution, and convex combination for the above subclass of harmonic functions.

The object of the present paper is to investigate coefficient estimates for functions belonging to the subclasses R p(α,β) and C p(α,β) of p-valent γ -prestarlike functions of order α and type β with negative coefficients. We obtain extreme points, distortion theorems, integral operators and radii of starlikeness and convexity for functions belonging to the classes R p(α,β) and C p (α,β). We also obtain several results for the modified Hadamard products of functions belonging to the classes R p(α,β) and C p(α,β).

In this paper, a new subclass of complex-valued harmonic univalent functions f(z)=h(z)+g(z)¯¯¯¯¯¯¯¯¯ in the open disk U={z:z∈C and |z|<1} defined by using a linear operator. We investigate coefficient condition, extreme points, distortion and convex combination for this subclass.

A new differential operator Dα,λ,γ,βm is introduced and a new subclass of analytic functions with negative coefficients defined by this operator is investigated. Some results on coefficient inequalities, distortion theorems and extreme points of analytic functions belonging to the subclass are obtained.

The purpose of this paper is to study subclasses of normalized harmonic functions with positive real part using fractional derivative. Sharp estimates for coefficients and distortion theorems are given.

In this paper, we introduce certain subclasses of meromorphic harmonic univalent functions, which are defined by using generalized (<i>p, q</i>)-post quantum calculus operators as well as subordination relationship. Sufficient coefficient conditions, extreme points, distortion bounds and convolution properties for functions belonging to the subclasses are obtained.

By making use of Carlson-Shaffer operator and P [ X, Y], we define new subclass of functions with negative co-efficients and obtain the coefficient bounds, extreme points, inclusion relations, distortion bounds and many more properties for functions belonging to generalized class TS (r, s, β, X, Y).

The purpose of the present paper is to introduce a new subclass of harmonic univalent functions associated with a $q$-Ruscheweyh derivative operator. A necessary and sufficient convolution condition for the functions to be in this class is obtained. Using this necessary and sufficient coefficient condition, results based on the extreme points, convexity and compactness for this class are also obtained.

Complex valued harmonic functions that are univalent and sense preserving in the unit disk U can be written in the form f = h + g ,w hereh and g are analytic in U. In this paper, we introduce a class HP(α), (α 0) of functions which are harmonic in U. We give sufficient coefficient conditions for normalized harmonic functions in HP(α). These conditions are also shown to be necessary when the coefficients are negative. This leads to distortion bounds and extreme points.

Properties and characteristics of certain subclasses of starlike functions of order [formula omitted

In this paper, we introduce and study a new subclass of analytic functions which are defined by means of a linear operator. Some results connected to coefficient estimates, growth and distortion theorems, radii of starlikeness, convexity close-to-convexity and integral means inequalities related to the subclass is obtained.