Results 21 to 30 of about 517,230 (334)
On initial coefficient inequalities for certain new subclasses of bi-univalent functions
Journal of the Egyptian Mathematical Society, 2017 In the present paper, we introduce two interesting subclasses of the class of bi-univalent functions defined on the open unit disk U and obtain improved estimates on the initial coefficients |a2|, |a3| and |a4| for the functions in these subclasses.
Uday H. Naik, Amol B. Patil
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Coefficient Bounds for Some Families of Bi-Univalent Functions with Missing Coefficients
Axioms, 2023 A branch of complex analysis with a rich history is geometric function theory, which first appeared in the early 20th century. The function theory deals with a variety of analytical tools to study the geometric features of complex-valued functions.
Ebrahim Analouei Adegani +3 more
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Convex and Starlike Functions Defined on the Subclass of the Class of the Univalent Functions $S$ with Order $2^{-r}$ [PDF]
Sahand Communications in Mathematical Analysis, 2022 In this paper, some conditions have been improved so that the function $g(z)$ is defined as $g(z)=1+\sum_{k\ge 2}^{\infty}a_{n+k}z^{n+k}$, which is analytic in unit disk $U$, can be in more specific subclasses of the $S$ class, which is the most ...
İsmet Yıldız +2 more
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On the Derivative of a Univalent Function [PDF]
Proceedings of the American Mathematical Society, 1953 Various results are known concerning the rate of growth of the derivative of a function f(z), analytic and univalent in the circle Izi
A. J. Lohwater, George Piranian
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Faber Polynomial Coefficient Estimates for Meromorphic Bi-Starlike Functions
International Journal of Mathematics and Mathematical Sciences, 2013 We consider meromorphic starlike univalent functions that are also bi-starlike and find Faber polynomial coefficient estimates for these types of functions. A function is said to be bi-starlike if both the function and its inverse are starlike univalent.
Samaneh G. Hamidi +2 more
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On the some subclasses of bi-univalent functions related to the Faber polynomial expansions and the Fibonacci numbers [PDF]
Rendiconti di Matematica e delle Sue Applicazioni, 2020 In this investigation, by using the Tremblay fractional derivative operator, we introduce a new class of bi-univalent functions based on the rule of subordination.
Şahsene Altınkaya, Sibel Yalçın
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On a class of univalent functions [PDF]
International Journal of Mathematics and Mathematical Sciences, 1999 We consider the class of univalent functions defined by the conditions f(z)/z ≠ 0 and |(z/f(z))′′| ≤ α, |z| < 1, where f(z) = z + ⋯ is analytic in |z| < 1 and 0 < α ≤ 2.
Dinggong Yang, Jin-Lin Liu
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Mathematics, 2019 In this investigation, by using the Komatu integral operator, we introduce the new class of bi-univalent functions based on the rule of subordination. Moreover, we use the Faber polynomial expansions and Fibonacci numbers to derive bounds for the general
Şahsene Altınkaya +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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Univalency of certain transform of univalent functions [PDF]
arXiv, 2022 We consider univalency problem in the unit disc $\mathbb D$ of the function $$g(z)=\frac{(z/f(z))-1}{-a_{2}},$$ where $f$ belongs to some classes of univalent functions in ${\mathbb D}$ and $a_{2}=\frac{f''(0)}{2}\neq 0$.
arxiv