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Introducing a new method we give sharp estimates of the Hermitian Toepliz determinants of third order for the class $\mathcal{S}$ of functions univalent in the unit disc. The new approach is also illustrated on some subclasses of the class…

Complex Variables · Mathematics 2021-04-23 Milutin Obradović , Nikola Tuneski

The classes of analytic univalent functions on the unit disk defined by $$ \mathcal{S}^*(\varphi)= \bigg\{ f \in \mathcal{A}: \frac{z f'(z)}{f(z)} \prec \varphi(z)\bigg\}$$ and $$ \mathcal{C}(\varphi)=\bigg\{ f \in \mathcal{A}: 1 + \frac{z…

Complex Variables · Mathematics 2025-05-19 Surya Giri

In the present paper two certain subclasses of the starlike functions associated with the vertical strip are considered. The main aim of this paper is to investigate some basic properties of these classes such as, subordination relations,…

Complex Variables · Mathematics 2018-11-26 Rahim Kargar

In this paper, we investigate three specific subclasses of Ma-Minda type convex functions: namely, convex functions of order $\alpha$, Janowski convex functions, and Robertson functions of normalized analytic functions defined in the open…

Complex Variables · Mathematics 2026-03-19 Md Firoz Ali , Lokenath Thakur

Motivated by applications to stochastic programming, we introduce and study the expected-integral functionals, which are mappings given in an integral form depending on two variables, the first a finite dimensional decision vector and the…

Optimization and Control · Mathematics 2021-06-15 Boris S. Mordukhovich , Pedro Pérez-Aros

The purpose of this paper is to introduce the logarithmic mean of two convex functionals that extends the logarithmic mean of two positive operators. Some inequalities involving this functional mean are discussed as well. The operator…

Functional Analysis · Mathematics 2020-10-07 Mustapha Raïssouli , Shigeru Furuichi

The object of this paper is to study relationship between successive coefficients of some subclasses of the class of univalent functions in the unit disk. the result obtained is sharp, and is used to provide a new, short proof of the…

Complex Variables · Mathematics 2010-04-21 K. O. Babalola

If f is a smooth function on a Hodge manifold, we construct a canonical sequence of real algebraic functions that converge to f in the smooth topology. The definition of of the approximants is inspired by Berezin-Toeplitz quantization. The…

Differential Geometry · Mathematics 2010-11-23 Alessandro Ghigi

The first objective of the paper is to estimate logarithmic partial derivative for meromorphic functions in several complex variables. Our estimations for logarithmic partial derivatives extend the results of Gundersen \cite{GG2} to the…

Complex Variables · Mathematics 2025-09-10 Junfeng Xu , Sujoy Majumder , 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…

Complex Variables · Mathematics 2023-04-26 Milutin Obradović , Nikola Tuneski

In this paper, we derive a local Carleman estimate for the complex second order elliptic operator with Lipschitz coefficients having jump discontinuities. Combing the result in [BL] and the arguments in [DcFLVW], we present an elementary…

Analysis of PDEs · Mathematics 2020-01-14 E. Francini , S. Vessella , J. -N. Wang

In this paper our aim is to deduce some sufficient (and necessary) conditions for the close-to-convexity of some special functions and their derivatives, like Bessel functions, Struve functions, and a particular case of Lommel functions of…

Classical Analysis and ODEs · Mathematics 2016-01-11 Árpád Baricz , Róbert Szász

We derive approximate formulas for the logarithmic de- rivative of the Selberg and Ruelle zeta functions over compact, even- dimensional, locally symmetric spaces of rank one. The obtained for- mulas are given in terms of the…

Number Theory · Mathematics 2014-10-29 Muharem Avdispahic , Dzenan Gusic

In this paper, we obtain the sharp bounds of the second Hankel determinant of logarithmic inverse coefficients for the strongly starlike and strongly convex functions of order alpha.

Complex Variables · Mathematics 2023-09-22 Vasudevarao Allu , Amal Shaji

In this paper we investigate Toeplitz and symmetric Toeplitz determinants of inverse functions for some classes of univalent functions and improve some previous results.

Complex Variables · Mathematics 2025-12-25 Milutin Obradović , Nikola Tuneski

We introduce a new method which enables us to calculate the coefficients of the poles of local zeta functions very precisely and prove some explicit formulas. Some vanishing theorems for the candidate poles of local zeta functions will be…

Complex Variables · Mathematics 2009-03-26 Toshihisa Okada , Kiyoshi Takeuchi

In this paper, we will give estimates for the logarithmic derivative $ \left\vert \frac{f^{\left( k\right) }\left( z\right) }{f\left( z\right) } \right\vert $ where $f$ is a meromorphic function in a region of the form $ D\left( 0,R\right)…

Complex Variables · Mathematics 2018-11-13 Saada Hamouda

In the present paper, the coefficient estimates are found for the class $\mathcal S^{*-1}(\alpha)$ consisting of inverses of functions in the class of univalent starlike functions of order $\alpha$ in $\mathcal D=\{z\in\mathbb C:|z|<1\}$.…

Complex Variables · Mathematics 2007-05-23 G. P. Kapoor , A. K. Mishra

Let $\mathcal{A}$ denote the class of functions $f$ that are analytic in the open unit disk $\mathbb{D}$ and satisfy the normalization conditions $f(0) = 0$ and $f'(0) = 1$. This paper investigates the inverse logarithmic coefficients…

Complex Variables · Mathematics 2026-03-19 Molla Basir Aahmed , Partha Pratim Roy

In this work, we consider certain class of bi-univalent functions related with shell-like curves related to $\kappa-$Fibonacci numbers. Further, we obtain the estimates of initial Taylor-Maclaurin coefficients (second and third…

Complex Variables · Mathematics 2020-01-24 N. Magesh , J. Nirmala , J. Yamini