Results 21 to 30 of about 536,183 (317)
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.
Obradović, Milutin +1 more
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Subordination by Univalent Functions [PDF]
Proceedings of the American Mathematical Society, 1981 Let K K be the class of functions f ( z ) = z + a 2 z 2 + ⋯ f(z) = z + {a_2}{z^2} + \cdots , which are regular and univalently convex in
Ram Singh, Sunder Singh
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On the growth of univalent functions. [PDF]
Michigan Mathematical Journal, 1968 Ch. Pommerenke
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Bounds for the Second Hankel Determinant of a General Subclass of Bi-Univalent Functions [PDF]
International Journal of Mathematical, Engineering and Management SciencesThe Hankel determinant, which plays a significant role in the theory of univalent functions, is investigated here in the context of bi-univalent analytic functions.
Mohamed Illafe +3 more
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Univalence Criteria for Locally Univalent Analytic Functions
Ukrainian Mathematical Journal, 2023 UDC 517.5 Suppose that p ( z ) = 1 + z ϕ ' ' ( z ) / ϕ ' ( z ) , where ϕ ( z ) is a locally univalent analytic function in the unit disk D with ϕ ( 0 ) = ϕ ' ( 1 ) - 1 = 0. We establish the lower and upper bounds for the best constants σ 0
Zhenyong Hu, Jinhua Fan, Xiaoyuan Wang
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Quasi-convex univalent functions
International Journal of Mathematics and Mathematical Sciences, 1980 In this paper, a new class of normalized univalent functions is introduced. The properties of this class and its relationship with some other subclasses of univalent functions are studied. The functions in this class are close-to-convex.
K. Inayat Noor, D. K. Thomas
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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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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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Coefficient Estimates for Certain Classes of Bi-Univalent Functions
International Journal of Mathematics and Mathematical Sciences, 2013 A function analytic in the open unit disk is said to be bi-univalent in if both the function and its inverse map are univalent there. The bi-univalency condition imposed on the functions analytic in makes the behavior of their coefficients ...
Jay M. Jahangiri, Samaneh G. Hamidi
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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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