Coefficient estimates for certain classes of meromorphic bi-univalent functions

We define a new class of meromorphic bi-univalent functions and use the Faber polynomial expansions to determine the coefficient bounds for such functions. Our results generalize and/or improve some of the previously known results. A meromorphic function is said to be bi-univalent in a given domain Δ if both the function and its inverse map are univalent there.     

Faber polynomial coefficient estimates for analytic bi-close-to-convex functions

Using the Faber polynomials, we obtain coefficient expansions for analytic bi-close-to-convex functions and determine coefficient estimates for such functions. We also demonstrate the unpredictable behavior of the early coefficients of subclasses of bi-univalent functions. A function is said to be bi-univalent in a domain if both the function and its inverse map are univalent there.     

Coefficient Estimates for Certain Subclasses of Bi-Univalent Ma-Minda Mocanu-Convex Functions

In this paper, we introduce and investigate a new subclass of the function class Σ of bi-univalent functions of the Mocanu-convex type defined in the open unit disk, satisfy Ma and Minda subordination conditions. Furthermore, we find estimates on the Taylor-Maclaurin coefficients |a2| and |a3| for functions in the new subclass introduced here. Further Application of Hohlov operator to this class is obtained. Several(known or new) consequences of the results are also pointed out.     

Faber polynomial coefficient estimates for a comprehensive subclass of analytic bi-univalent functions

In this work, considering a general subclass of analytic bi-univalent functions, we determine estimates for the general Taylor–Maclaurin coefficients of the functions in this class. For this purpose, we use the Faber polynomial expansions. In certain cases, our estimates improve some of those existing coefficient bounds.     

Ma jorization Results and Coefficients Bounds for a Class of Univalent Functions Asso ciated with Operator

In this paper we introduce a new general subclass n,g ∑ a,λ(A, B,α) of univalent func-tions related the known integral operator and differential operator. Some majorization re-sults for n,g ∑ a,λ(A, B, 1) as well as the other functions are given. Furthermore, we find the coefficients bounds on|a2|and|a3|for functions in?n,g ∑ a,λ(A1, B1, A2, B2,α1,α2), which is the bi-univalent functions defined by n,g ∑ a,λ(A, B,α) and subordination. By giving specific values of the parameters of our main results, several(known or new) consequences of main results are also discussed.     

与条形区域有关的双向单叶解析函数子类的系数估计

本文引入了条形区域内由Salagean算子刻画的解析函数新子类, 讨论了该函数子类的系数估计、Fekete-Szego不等式以及与该函数子类有关的双向单叶函数的系数估计, 所得结果推广了前人的一些工作.     

A new class of Salagean-type harmonic univalent functions

We define and investigate a new class of Salagean-type harmonic univalent functions. We obtain coefficient conditions, extreme points, distortion bounds, convex combination and radii of convex for the above class of harmonic univalent functions.     

一类新的单叶调和函数(英文)

A complex-valued harmonic function that is univalent and sense preserving in the unit disk U can be written in the form of f = h + g,where h and g are analytic in U.We define and investigate a new class LH_λ(α,β) by generalized Salagean operator of harmonic univalent functions.We give sufficient coefficient conditions for normalized harmonic functions in the class LH_λ(α,β).These conditions are also shown to be necessary when the coefficients are negative.This leads to distortion bounds and extreme points.     

On the Coefficients of Several Classes of Bi-Univalent Functions

In this paper, we investigate the bounds of the coefficients of several classes of bi-univalent functions. The results presented in this paper improve or generalize the recent works of other authors.     

双单叶函数某个子类的Faber多项式系数估计

The main objective of this paper is to derive the upper bounds for the coefficients of functions in a subclass of analytic and bi-univalent functions associated with Faber polynomials.The consequences presented here point out and correct the errors of some earlier results.     

ON THE COEFFICIENTS OF SEVERAL CLASSES OF BI-UNIVALENT FUNCTIONS

In this paper, we investigate the bounds of the coefficients of several classes of bi-univalent functions. The results presented in this paper improve of generalize the recent works of other authors.     

Coefficient estimates for a certain class of analytic and bi-univalent functions defined by fractional derivative

We introduce and investigate a subclass of analytic and bi-univalent functions defined by a fractional derivative operator in the open unit disk. Using the Faber polynomial expansions, we obtain upper bounds for the coefficients of functions belonging to this class.     

用Salagean算子定义的缺系数的单叶调和函数类

本文研究了用Salagean算子定义的缺系数单叶调和函数类.利用从属关系和算子理论得到类中函数的系数估计、极值点、偏差定理、卷积性质、凸性组合与凸半径,推广了已有的一些结果.     

与广义$(p,q)$量子积分算子有关的调和单叶函数

利用广义的$(p,q)$量子积分算子, 本文引入了与Janowski函数相关的调和单叶函数的某些子类, 得到了这些函数类的充分系数条件, 极值点, 偏差估计及部分和等性质.     

A CLASS OF HARMONIC STARLIKE FUNCTIONS WITH RESPECT TO SYMMETRIC POINTS ASSOCIATED WITH WRIGHT GENERALIZED HYPERGEOMETRIC FUNCTION

Making use of Wright operator we introduce a new class of complex-valued harmonic functions with respect to symmetric points which are orientation preserving, univalent and starlike. We obtain coefficient conditions, extreme points, distortion bounds, and convex combination.     

几类亚纯双单叶函数的系数估计

研究了几类亚纯双单叶函数的系数估计,所得结果改进或推广了部分作者的结论.     

On the Coefficients of Several Classes of Bi-univalent Functions Defined by Convolution

In this paper, we introduce several new subclasses of the function class Σ of bi-univalent functions analytic in the open unit disc defined by convolution.Furthermore, we investigate the bounds of the coefficients |a2| and |a3| for functions in these new subclasses. The results presented in this paper improve or generalize the recent works of other authors.     

由卷积和从属关系刻画的单叶调和函数某些子类

Let SH be the class of functions f = h + ˉg that are harmonic univalent and sensepreserving in the open unit disk U = {z ∈ C : |z| 1} for which f(0) = f′(0)-1 = 0. In the present paper, we introduce some new subclasses of SH consisting of univalent and sensepreserving functions defined by convolution and subordination. Sufficient coefficient conditions,distortion bounds, extreme points and convolution properties for functions of these classes are obtained. Also, we discuss the radii of starlikeness and convexity.     

Estimates for inverse coefficients of univalent functions from integral means

The purpose of this note is to point out that sharp coefficient bounds for the inverses of univalent functions from certain families are fairly direct corollaries of results on integral means. As an example, in §1 the method is applied to the familiar schlicht classS. The resulting coefficient estimates for the inverses of functions inS were first obtained by K. Löwner. Following this prototype, in §2 we obtain corresponding results, which are new, for a classS(p) of meromorphic schlicht functions in |z|<1.     

Boundedness properties of univalent functions with positive coefficients

The present contribution investigates sharp lower bounds of the real parts of certain types of rational functions defined in terms of functions which are analytic and univalent in the open unit disk, and which also involve the familiar fractional derivative operator. Some worthwhile consequences of the main results are also pointed out.