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Related papers: Estimates for the Initial Coefficients of Bi-univa…

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We consider holomorphic functions on the unit disc whose images are contained in a strip of the complex plane. Under an additional condition, such functions are constants. We also consider appropriate operator valued versions. Applications…

Functional Analysis · Mathematics 2024-06-12 Tirthankar Bhattacharyya , Anthony G. O'Farrell , Shubham Rastogi , Vijaya Kumar U

Let ${\mathcal A}$ be the class of functions $f$ that are analytic in the unit disk ${\mathbb D}$ and normalized such that $f(z)=z+a_2z^2+a_3z^3+\cdots$. Let $0<\lambda\le1$ and \[ {\mathcal U}(\lambda) = \left\{ f\in{\mathcal A}: \left…

Complex Variables · Mathematics 2021-04-26 Milutin Obradović , Nikola Tuneski

In this present investigation, we introduce the new class R of bi-univalent functions defined by using the Tremblay fractional derivative operator. Additionally, we use the Faber polynomial expansions and Fibonacci numbers to derive bounds…

Complex Variables · Mathematics 2019-01-23 Sahsene Altinkaya , Samaneh G. Hamidi , Jay M. Jahangiri , Sibel Yalcin

Let $\mathcal{A}$ denote the class of normalized analytic functions $f$ in the open unit disk defined as $ \mathbb{D}:=\{z\in\mathbb{C}:|z|<1\} $ with $f(0)=0$ and $f'(0)=1$. A function $f\in\mathcal{A}$ is said to be starlike if…

Complex Variables · Mathematics 2026-04-28 Vasudevarao Allu , Shobhit Kumar

We define generalized bivariate polynomials, from which upon specification of initial conditions the bivariate Fibonacci and Lucas polynomials are obtained. Using essentially a matrix approach we derive identities and inequalities that in…

Combinatorics · Mathematics 2007-05-23 Mario Catalani

A canonical model, analogous to the one for contraction operators, is introduced for bi-isometries, two commuting isometries on a Hilbert space. This model involves a contractive analytic operator-valued function on the unit disk. Various…

Functional Analysis · Mathematics 2010-12-07 Hari Bercovici , Ronald G. Douglas , Ciprian Foias

The purpose of this article is to study Bohr inequalities involving the absolute values of the coefficients of an operator valued function. To be more specific, we establish an operator valued analogue of a classical result regarding the…

Complex Variables · Mathematics 2020-03-13 Bappaditya Bhowmik , Nilanjan Das

Our objective in this paper is to introduce and investigate a newly-constructed subclass of normalized analytic and bi-univalent functions by means of the Chebyshev polynomials of the second kind. Upper bounds for the second and third…

Complex Variables · Mathematics 2021-02-18 Feras Yousef , Somaia Alroud , Mohamed Illafe

The main objective of the present article is to make interconnection between the Generalized Hyergeometric series and some subclasses of normalized analytic functions with positive(Tailor's) coefficients in the open unit disc $\mathbb{D}…

Complex Variables · Mathematics 2023-08-09 K. Chandrasekran , D. J. Prabhakaran

We consider two natural gradings on the space of symmetric functions: by degree and by length. We introduce a differential operator $T$ that leaves the components of this double grading invariant and exhibit a basis of bihomogeneous…

Combinatorics · Mathematics 2021-07-01 Yuly Billig

We intend to derive the moment and exponential tail estimates for the so-called bivariate or more generally multivariate functional operations, not necessary to be linear or even multilinear. We will show also the strong or at last weak…

Functional Analysis · Mathematics 2018-05-08 E. Ostrovsky , L. Sirota

Let function $f$ be analytic in the unit disk ${\mathbb D}$ and be normalized so that $f(z)=z+a_2z^2+a_3z^3+\cdots$. In this paper we give sharp bounds of the modulus of its second, third and fourth coefficient, if $f$ satisfies \[…

Complex Variables · Mathematics 2018-10-15 Milutin Obradovic , Nikola Tuneski

The f-invariant is a higher version of the e-invariant that takes values in the divided congruences between modular forms; in the situation of a cartesian product of two framed manifolds, the f-invariant can actually be computed from the…

Algebraic Topology · Mathematics 2009-12-16 Hanno von Bodecker

Based on the total integrability we first define an integral of a real valued function f as an interval function associated to its antiderivative F. By introducing the concept of the residue of a function into the real analysis, the…

Classical Analysis and ODEs · Mathematics 2014-09-29 Branko Saric

In this paper, the authors first consider the bidirectional estimates of several typical integrals. As some applications of these integral estimates, the authors investigate the pointwise multipliers from the normal weight general function…

Functional Analysis · Mathematics 2024-12-25 Xuejun Zhang , Hongxin Chen , Min Zhou , Yuting Guo , Pengcheng Tang

Computing explicitly the {\epsilon}-subdifferential of a proper function amounts to computing the level set of a convex function namely the conjugate minus a linear function. The resulting theoretical algorithm is applied to the the class…

Optimization and Control · Mathematics 2017-09-26 Anuj Bajaj , Warren Hare , Yves Lucet

We show that the coefficients of rational 2-functions are contained in an abelian number field. More precisely, we show that the poles of such functions are poles of order one and given by roots of unity and rational residue.

Number Theory · Mathematics 2021-03-10 Felipe Müller

We obtain formulas for the coefficients of positive and negative powers of a partial theta function.

Number Theory · Mathematics 2024-08-27 Johann Cigler

In the paper we find effective formulas for the invariant functions, appearing in the theory of several complex variables, of the elementary Reinhardt domains. This gives us the first example of a large family of domains for which the…

Complex Variables · Mathematics 2008-02-03 Peter Pflug , Wlodzimierz Zwonek

We present a simplified integral of functions of several variables. Although less general than the Riemann integral, most functions of practical interest are still integrable. On the other hand, the basic integral theorems can be obtained…

Classical Analysis and ODEs · Mathematics 2007-12-05 Ágnes M. Backhausz , Vilmos Komornik , Tivadar Szilágyi