Results 31 to 40 of about 5,426 (207)
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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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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Majorization for certain classes of meromorphic functions defined by integral operator
, 2016 Here we investigate a majorization problem involving starlike meromorphic functions of complex order belonging to a certain subclass of meromorphic univalent functions defined by an integral operator introduced recently by ...
Goyal, S. P., Goswami, Pranay
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On the coefficient domains of univalent functions
International Journal of Mathematics and Mathematical Sciences, 1990 Coefficient domains for functions whose derivative has positive real part in the interior of an ellipse are given in this paper.
M. M. Elhosh
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Axioms, 2022 The logarithmic coefficients are very essential in the problems of univalent functions theory. The importance of the logarithmic coefficients is due to the fact that the bounds on logarithmic coefficients of f can transfer to the Taylor coefficients of ...
Sevtap Sümer Eker +3 more
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The Coefficients Of Functions With Positive Real Part And Some Special Classes Of Univalent Functions. [PDF]
, 2003 Several special classes of univalent functions f in the unit disk U are characterized by the quantity zf'(z)/ f (z) lies in a given region in the right-half plane.
M. Ali, Rosihan
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On the asymptotic Bieberbach conjecture
International Journal of Mathematics and Mathematical Sciences, 1982 The set S consists of complex functions f, univalent in the open unit disk, with f(0)=f'(0)-1=0. We use the asymptotic behavior of the positive semidefinite FitzGerald matrix to show that there is an absolute constant N0 such that, for any f(z)=z+?n ...
Mauriso Alves, Armando J. P. Cavalcante
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International Journal of Mathematics and Mathematical Sciences, 2012 Let R(𝔻) be the algebra generated in Sobolev space W22(𝔻) by the rational functions with poles outside the unit disk 𝔻¯. In this paper, we study the similarity invariant of the multiplication operators Mg in ℒ(R(𝔻)), when g is univalent analytic on 𝔻 or ...
Ruifang Zhao
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Extremal properties of extreme and support points of univalent functions with montel normalization
, 2008 Let U = {z : vertical bar z vertical bar < 1} be the unit disk. The Montel class, M(a), is the class of functions f (z) = a(1)z + a(2)z(2) +..., which are analytic and univalent in the unit disk and satisfy the conditions f (0) = 0 and f (a) = a, (0 ...
UÇAR, FARUK
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Coefficients Of The Inverse Of Strongly Starlike Functions. [PDF]
, 2003 For the class of strongly starlike functions, sharp bounds on the first four coefficients of the inverse functions are determined. A sharp estimate for the Fekete-Szego coefficient functional is also obtained.
M. Ali, Roslhan
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