Initial Coefficients of Biunivalent Functions
Abstract and Applied Analysis, 2014 An analytic function f defined on the open unit disk is biunivalent if the function f and its inverse f-1 are univalent in 𝔻. Estimates for the initial coefficients of biunivalent functions f are investigated when f and f-1, respectively, belong to some ...
See Keong Lee +2 more
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On the coefficients of R-univalent functions [PDF]
Duke Mathematical Journal, 1955 (4) | an| < 41 di n, f(z) 5 d(I zI < 1). Because of d|I d 1/4, (4) is weaker than the Bieberbach conjecture but, as shown by the function f(z) =z(1 -Z)-2 =z+2z2+3z3+ (f(z)05-1/4), it would still be sharp. In the present note we shall show that the truth of Littlewood's conjecture (4) would follow from the proof of the asymptotic result (3).
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Bounds For the Coefficients of Two New Subclasses of Bi-Univalent Functions
Science Journal of University of Zakho, 2022 This article discusses two new subclasses of the bi-univalent functions category ∑ in the open unit disk . The primary goal of the article is to obtain estimations of the coefficients and for the functions that are within these two new subclasses.
khalid Ibrahim Abdullah +1 more
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On a subclass of univalent functions II [PDF]
Annales Polonici Mathematici, 1983 [For part I see the review above.] Let f be analytic in the unit disc E with \(f(0)=f'(0)-1=0,\) and \(f(z)f'(z)/z\neq 0\) for z in E. Using the standard technique the authors have obtained an integral representation formula for \(f\in C(\alpha,\lambda)\) and estimates for the coefficients of \(f\in C(\alpha,\lambda)\), where \(C(\alpha\),\(\lambda ...
Padmanabhan, K. S., Bharati, R.
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On the Existence of Functions being Univalent in Half-plane together with their Derivatives
Nonlinear Analysis, 2001 In articles [1]-[3] a class of functions being univalent in unit disc with all their derivatives was investigated. It was proved such functions exist and must be the entire functions of exponential type.
J. Kirjackis
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Estimating coefficients for certain subclasses of meromorphic and bi-univalent functions
Journal of Inequalities and Applications, 2018 In the present paper, we introduce two interesting subclasses of meromorphic and bi-univalent functions defined on Δ={z:z∈C ...
F. Müge Sakar
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On a class of univalent functions
Applied Mathematics Letters, 2012 AbstractLet A be the class of analytic functions in the unit disk D with the normalization f(0)=f′(0)−1=0. Denote by N the class of functions f∈A which satisfy the condition |−z3(zf(z))‴+f′(z)(zf(z))2−1|≤1,z∈D. We show that functions in N are univalent in D but not necessarily starlike.
Milutin Obradovic, Saminathan Ponnusamy
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Certain Classes of Univalent Functions With Negative Coefficients Defined By General Linear Operator
Tikrit Journal of Pure Science, 2019 In this study, a subclass of an univalent function with negative coefficients which is defined by anew general Linear operator have been introduced.
Mazin Sh.Mahmoud +2 more
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Meromorphic univalent function with negative coefficient
International Journal of Mathematics and Mathematical Sciences, 1994 Let Mn be the classes of regular functions f(z)=z−1+a0+a1z+… defined in the annulus ...
A. Dernek
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Application of Gegenbauer Polynomials with Two Variables to Bi-univalency of Generalized Discrete Probability Distribution Via Zero-Truncated Poisson Distribution Series [PDF]
Sahand Communications in Mathematical AnalysisThe present study is unique in exploring bi-univalent functions, which has recently garnered attention from many researchers in Geometric Function Theory (GFT).
Tunji Ibrahim Awolere +2 more
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