English
Related papers

Related papers: Coefficient estimates of certain subclasses of ana…

200 papers

In this study, a subclass of an univalent function with negative coefficients which is defined by a new general Linear operator have been introduced. The sharp results for coefficients estimators, distortion and closure bounds, Hadamard…

Complex Variables · Mathematics 2020-05-15 Mazin Sh. Mahmoud , Abdul Rahman S. Juma , Raheam A. Mansor Al-Saphory

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…

Complex Variables · Mathematics 2026-05-20 Pradip Das , Nabadwip Sarkar

For $\alpha\ge 0$, let $\mathcal{W}(\alpha)$ be the class of all analytic functions in the unit disk $\mathbb{D}$ with normalization $f(0) = 0 $ and $ f'(0) = 1 $ that satisfy the relation $Re\,\{f'(z) + \alpha z f''(z)\} > 0$. This article…

Complex Variables · Mathematics 2026-05-20 Chayani Dhara , Nirupam Ghosh

Let $f$ be analytic in the unit disk $\mathbb D$ and normalized so that $f(z)=z+a_2z^2+a_3z^3+\cdots$. In this paper, we give upper bounds of the Hankel determinant of second order for the classes of starlike functions of order $\alpha$,…

Complex Variables · Mathematics 2019-12-30 Milutin Obradovic , Nikola Tuneski

The main purpose of this paper is to introduce a new comprehensive subclass of analytic close-to-convex functions and derive Fekete-Szeg\"o inequalities for functions belonging to this new class by using a different way. Various known…

Complex Variables · Mathematics 2019-03-08 Serap Bulut

We consider a family of all analytic and univalent functions (i.e., one-to-one) in the unit disk $\mathbb{D}:=\{z\in \mathbb{C}:|z|<1\}$ of the form $f(z)=z+a_2z^2+a_3z^3+\cdots$. In this paper, we obtain the sharp bounds of the second…

Complex Variables · Mathematics 2021-12-09 Vasudevarao Allu , Vibhuti Arora

Let $E$ be the open unit disk $\{z\in \mathbb{C}: |z|<1\}$. Let $A$ be the class of analytic functions in $E$, which have the form $f(z)=z+a_2z^2+...$. We define operators $L_n^\sigma\colon A\to A$ using the convolution *. Using these…

Complex Variables · Mathematics 2009-11-04 K. O. Babalola

In this paper, we show that for a broad class of pseudoconvex formal-analytic arithmetic surfaces over $\text{Spec}(\mathbb{Z})$, those which admit a nonconstant monic such regular function, that a conjecture of Bost-Charles that the ring…

Complex Variables · Mathematics 2025-12-12 Samuel Goodman

In this paper, sharp bounds are established for the second Hankel determinant of logarithmic coefficients for normalised analytic functions satisfying certain differential inequality.

Complex Variables · Mathematics 2022-08-16 Mridula Mundalia , S. Sivaprasad Kumar

We introduce a class of analytic functions subordinate to the function $1+\sinh \left( z\right) $ and obtain various necessary and sufficient conditions for functions to be in the class. These conditions mainly comprise of the coefficient…

Complex Variables · Mathematics 2020-11-11 S. Sivaprasad Kumar , Muhammad Ghaffar Khan , Bakhtiar Ahmad , Wali Khan Mashwani

In this paper, we introduce and investigate two new subclasses of analytic functions in the open unit disk in the complex plane. Several interesting properties of the functions belonging to these classes are examined. Here, sufficient, and…

Complex Variables · Mathematics 2017-04-18 Nizami Mustafa

This is a tutorial introduction to the functional analysis mathematics needed in many physical problems, such as in waves in continuous media. Functional analysis takes us beyond finite matrices, allowing us to work with infinite sets of…

Functional Analysis · Mathematics 2019-04-15 David A. B. Miller

In this paper, we define a new subclass of $k$-uniformly starlike functions of order $\gamma,\ (0\leq\gamma<1)$ by using certain generalized $q$-integral operator. We explore geometric interpretation of the functions in this class by…

Complex Variables · Mathematics 2021-01-14 Om Ahuja , Asena Çetinkaya , Naveen Kumar Jain

We introduce the notion of rationality for hyperholomorphic functions (functions in the kernel of the Cauchy-Fueter operator). Following the case of one complex variable, we give three equivalent definitions: the first in terms of…

Functional Analysis · Mathematics 2007-05-23 D. Alpay , M. Shapiro , D. Volok

In this article, we prove the existence of extremal functions in higher-order affine Sobolev inequalities. Proofs rely on concentration-compactness methods in spaces of integer or fractional regularity. The tools we use, available in spaces…

Functional Analysis · Mathematics 2026-04-02 Tristan Bullion-Gauthier

For $0<\lambda\le 1$, let $\mathcal{U}(\lambda)$ be the class analytic functions $f(z)= z+\sum_{n=2}^{\infty}a_n z^n$ in the unit disk $\mathbb{D}$ satisfying $|f'(z)(z/f(z))^2-1|<\lambda$ and $\mathcal{U}:=\mathcal{U}(1)$. In the present…

Complex Variables · Mathematics 2020-06-30 Md Firoz Ali , Vasudevarao Allu , Hiroshi Yanagihara

After carrying out an overview on the non Euclidean geometrical setting suitable for the study of Kolmogorov operators with rough coefficients, we list some properties of the functional space $\mathcal{W}$, mirroring the classical $H^1$…

Analysis of PDEs · Mathematics 2023-04-04 Francesca Anceschi , Mirco Piccinini , Annalaura Rebucci

Assume $z_0$ lies in the open unit disk $\mathbb{D}$ and $g$ is an analytic self-map of $\mathbb{D}$. We will determine the region of values of $g''(z_0)$ in terms of $z_0$, $g(z_0)$ and the hyperbolic derivative of $g$ at $z_0$, and give…

Complex Variables · Mathematics 2024-03-18 Gangqiang Chen

Estimating the coefficient functionals on various classes of holomorphic functions traditionally forms an important field of geometric complex analysis and its mathematical and physical applications. These coefficients reflect fundamental…

Complex Variables · Mathematics 2025-07-29 Samuel L. Krushkal

We study the question of the existence of a dual extremal function for a bounded matrix function on the unit circle in connection with the problem of approximation by analytic matrix functions. We characterize the class of matrix functions,…

Functional Analysis · Mathematics 2008-01-03 V. V. Peller