Results 31 to 40 of about 134 (91)
Mathematics, 2023 The main goal of this investigation is to obtain sharp upper bounds for Fekete-Szegö functional and the third Hankel determinant for a certain subclass SL∗u,v,α of holomorphic functions defined by the Carlson-Shaffer operator in the unit disk.
Halit Orhan +2 more
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The Fekete-Szegö Problem for p-Valently Janowski Starlike and Convex Functions
International Journal of Mathematics and Mathematical Sciences, 2011 For p-valently Janowski starlike and convex functions defined by applying subordination for the generalized Janowski function, the sharp upper bounds of a functional |ap+2−μa2p+1| related to the Fekete-Szegö problem are given.
Toshio Hayami, Shigeyoshi Owa
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Coefficient estimates for Ruscheweyh derivatives
International Journal of Mathematics and Mathematical Sciences, 2004 We consider functions f, analytic in the unit disc and of the normalized form f(z)=z+∑n=2∞anzn. For functions f∈R¯δ(β), the class of functions involving the Ruscheweyh derivatives operator, we give sharp upper bounds for the Fekete-Szegö functional |a3 ...
Maslina Darus, Ajab Akbarally
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Starlike Functions Based on Ruscheweyh q−Differential Operator defined in Janowski Domain
Fractal and Fractional, 2023 In this paper, we make use of the concept of q−calculus in the theory of univalent functions, to obtain the bounds for certain coefficient functional problems of Janowski type starlike functions and to find the Fekete–Szegö functional.
Luminiţa-Ioana Cotîrlǎ +1 more
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International Journal of Mathematics and Mathematical Sciences, 2019 The aim of this paper is to study certain subclasses of bi-univalent functions defined by generalized Sãlãgean differential operator related to shell-like curves connected with Fibonacci numbers.
Gurmeet Singh +2 more
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Axioms, 2022 The present paper introduces a new class of bi-univalent functions defined on a symmetric domain using Gegenbauer polynomials. For functions in this class, we have derived the estimates of the Taylor–Maclaurin coefficients, a2 and a3, and the Fekete ...
Mohamed Illafe +2 more
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Mathematics, 2023 We utilize quasi-subordination to analyze and introduce several new classes, and we construct a new operator by combining the error function and q-convolution.
Sheza M. El-Deeb +1 more
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A Two‐Parameter Subclass of q‐Starlike Functions Associated With 1−sinz/cosz
Journal of Function Spaces, Volume 2026, Issue 1, 2026.Using the real parameters λ and τ with −1 ≤ τ < λ < 1, a generalized q−extension ψqz;λ,τ of the function ψz=1−sinz/cosz, in O´=z∈ℂ:z<1, is defined. The function ψqz;λ,τ is then used as a subordination function to construct a novel subclass; STq∗λ,τ of q−starlike functions.
Nehad Ali Shah +4 more
wiley +1 more source
Coefficient Inequalities Related With Apple‐Like Functions
Journal of Function Spaces, Volume 2026, Issue 1, 2026.Several subfamilies of Ma and Minda starlike and convex functions have been examined differently through individual generating functions in the literature. However, little or no effort has been devoted to subfamily arising from the product of these generating functions.
Aiman Sana +3 more
wiley +1 more source
Journal of Function Spaces, Volume 2026, Issue 1, 2026.In geometric function theory and complex analysis, analytic functions exhibiting geometric symmetry play a fundamental role. However, investigations concerning multileaf domains, particularly those with fivefold rotational symmetry, have been relatively limited.
Suad Al-Mayyahi +4 more
wiley +1 more source