中文
相关论文

相关论文: On the Fekete-Szeg\"o problem for concave univalen…

200 篇论文

The article deals with the class ${\mathcal F}_{\alpha }$ consisting of non-vanishing functions $f$ that are analytic and univalent in $\ID$ such that the complement $\IC\backslash f(\ID) $ is a convex set, $f(1)=\infty ,$ $f(0)=1$ and the…

复变函数 · 数学 2016-06-06 Y. Abu Muhanna , S. Ponnusamy

We consider again a classical theorem relating capacities and algebraic integers and the question of the simultaneous approximation of $ n-1$ different complex numbers by conjugate algebraic integers of degree $n$.

经典分析与常微分方程 · 数学 2026-05-27 Thérèse Fallièro

In this paper we establish the coefficient bodies for a wide class of families of inverse functions. We also completely describe those functions that provide boundary points of that bodies in small dimensions. As an application we get sharp…

复变函数 · 数学 2020-12-15 Mark Elin , Fiana Jacobzon

In the present article, our aim is to examine some useful problems including the convolution problem, sufficiency criteria, coefficient estimates and Fekete-Szego type inequalities for a new subfamily of analytic and multivalent functions…

经典分析与常微分方程 · 数学 2019-07-19 Lei Shi , Qaiser Khan , Gautam Srivastava , Jin-Lin Liu , Muhammad Arif

We consider a new subclass $\widetilde{\mathcal{K}}_u$ of close-to-convex functions in the unit disk $\mathbb{D}:=\{z\in\mathbb{C}:|z|<1\}$. For this class, we obtain sharp estimates of the Fekete-Szeg\"{o} problem, growth and distortion…

复变函数 · 数学 2025-05-20 Md Nurezzaman

A typical quandary in geometric functions theory is to study a functional composed of amalgamations of the coefficients of the pristine function. Conventionally, there is a parameter over which the extremal value of the functional is…

复变函数 · 数学 2018-09-19 P. Gochhayat , A. Prajapati , A. K. Sahoo

For convex univalent functions we give instances where the sharp bound for various coefficient functionals are identical to those for the corresponding bound for the inverse function. We give instances where the sharp bounds differ and also…

复变函数 · 数学 2022-12-12 Derek K. Thomas

In this paper, we introduce a subclass of close-to-convex functions defined in the open unit disk. We obtain the inclusion relationships, coefficient estimates and Fekete-Szego inequality. The results presented here would provide extension…

复变函数 · 数学 2016-06-02 Yao Liang Chung , See Keong Lee , Maisarah Haji Mohd

In this paper we introduce the Fekete--Szeg\"{o} type mapping in the open unit ball of a complex Banach space. % and study its geometric and analytical properties. All previously studied modifications of the Fekete--Szeg\"{o} functional are…

复变函数 · 数学 2024-06-06 Mark Elin , Fiana Jacobzon

Let $Co(\alpha)$ denote the class of concave univalent functions in the unit disk $\ID$. Each function $f\in Co(\alpha)$ maps the unit disk $\ID$ onto the complement of an unbounded convex set. In this paper we find the exact disk of…

复变函数 · 数学 2010-08-31 B. Bhowmik , S. Ponnusamy , K-J. Wirths

We extend our definition (in a recent paper \cite{KB}) of the coefficient determinants of analytic mappings of the unit disk to include many Fekete-Szeg$\ddot{o}$-type parameters, and compute the best possible bounds on certain specific…

复变函数 · 数学 2013-11-07 K. O. Babalola

Recently, in their pioneering work on the subject of bi-univalent functions, Srivastava et al. \cite{HMS-AKM-PG} actually revived the study of the coefficient problems involving bi-univalent functions. Inspired by the pioneering work of…

复变函数 · 数学 2018-10-16 N. Magesh , V. K. Balaji , C. Abirami

The purpose of this paper is to consider coefficient estimates in a class of functions $\mathfrak{G}_{\vartheta}^{\kappa}(\mathcal{X},\varkappa)$ consisting of analytic functions $f$ normalized by $f(0)=f'(0)-1=0$\ in the open unit disk…

复变函数 · 数学 2023-08-02 Gangadharan Murugusundaramoorthy , kaliappan Vijaya , Hijaz Ahmad

The Chebyshev polynomials are utilized in this study to define the subclass of the bi-univalent function. Also, Chebyshev polynomial bounds and Fekete-Szego inequalities for functions defined in the classes are established.

复变函数 · 数学 2022-09-20 G. M. Birajdar , N. D. Sangle

In this paper, we investigate the inverse logarithmic coefficients associated with the class $\mathcal{C}_e$ of analytic and univalent functions satisfying the subordination condition \[ 1+\frac{z f''(z)}{f'(z)} \prec e^z, \quad…

复变函数 · 数学 2026-05-20 Pradip Das , Nabadwip Sarkar

Let $\mathcal{U(\alpha, \lambda)}$, $0<\alpha <1$, $0 < \lambda <1$ be the class of functions $f(z)=z+a_{2}z^{2}+a_{3}z^{3}+\cdots$ satisfying $$\left|\left(\frac{z}{f(z)}\right)^{1+\alpha}f'(z)-1\right|<\lambda$$ in the unit disc ${\mathbb…

复变函数 · 数学 2023-04-26 Milutin Obradović , Nikola Tuneski

In this paper, we study extremal problems for coefficient functionals associated with a distinguished subclass of holomorphic semigroup generators, denoted by $\mathcal{A}_{\beta}$ ($0 \le \beta \le 1$), defined on the unit disk…

复变函数 · 数学 2026-04-29 Sanju Mandal , Molla Basir Ahamed

In this paper, we generalize and investigate Bohr-Rogosinski's inequalities and the Bohr-Rogosinski phenomenon for the subfamilies of univalent (i.e., one-to-one) functions defined on unit disk $\mathbb{D}:=\{z\in \mathbb{C}:|z|<1 \}$ which…

复变函数 · 数学 2022-05-02 Vasudevarao Allu , Vibhuti Arora

In this paper, we introduce and investigate a new subclass of bi-prestarlike functions defined in the open unit disk, associated with Chebyshev Polynomials. Furthermore, we find estimates of first two coefficients of functions in these…

复变函数 · 数学 2020-03-24 Hatun Ozlem Guney , G. Murugusundaramoorthy , K. Vijaya , K. Thilagavathi

In 2011, Sok\'{o}{\l} (Comput. Math. Appl. 62, 611--619) introduced and studied the class $\mathcal{SK}(\alpha)$ as a certain subclass of starlike functions, consists of all functions $f$ ($f(0)=0=f'(0)-1$) which satisfy in the following…

复变函数 · 数学 2018-04-19 R. Kargar , H. Mahzoon , N. Kanzi