scholarly journals Upper Bounds For Fekete-Szego Functions And The Second Hankel Determinant for A Class of Starlike Functions.

2017 ◽  
Vol 13 (02) ◽  
pp. 34-39
Author(s):  
Bello R. A ◽  
Opoola T. O
Keyword(s):  
Starlike Functions ◽  
Upper Bounds ◽  
Hankel Determinant ◽  
Second Hankel Determinant

scholarly journals Second Hankel determinant problem for k-bi-starlike functions

Filomat ◽  
2017 ◽  
Vol 31 (12) ◽  
pp. 3897-3904 ◽  
Author(s):  
Halit Orhan ◽  
Evrim Toklu ◽  
Ekrem Kadıoğlu
Keyword(s):  
Starlike Functions ◽  
Upper Bounds ◽  
Hankel Determinant ◽  
Derivative Operator ◽  
Second Hankel Determinant

In this paper we introduce and study some properties of k-bi-starlike functions defined by making use of the S?l?gean derivative operator. Upper bounds on the second Hankel determinant for k-bi-starlike functions are investigated. Relevant connections of the results presented here with various well-known results are briefly indicated.

scholarly journals Hankel determinant for a class of analytic functions of complex order defined by convolution

2015 ◽  
Vol 69 (2) ◽  
pp. 47
Author(s):  
S. M. El-Deeb ◽  
M. K. Aouf
Keyword(s):  
Analytic Functions ◽  
Upper Bounds ◽  
Hankel Determinant ◽  
Complex Order ◽  
Second Hankel Determinant

In this paper, we obtain the Fekete-Szego inequalities for the functions of complex order defined by convolution. Also, we find upper bounds for the second Hankel determinant \(|a_2a_4-a_3^2|\) for functions belonging to the class \(S_{\gamma}^b(g(z);A,B)\).

scholarly journals A Study of Fourth-Order Hankel Determinants for Starlike Functions Connected with the Sine Function

2021 ◽  
Vol 2021 ◽  
pp. 1-8
Author(s):  
Hai-Yan Zhang ◽  
Huo Tang
Keyword(s):  
Fourth Order ◽  
Starlike Functions ◽  
Function Class ◽  
Upper Bounds ◽  
Sine Function ◽  
Hankel Determinant ◽  
Hankel Determinants

In this paper, upper bounds for the fourth-order Hankel determinant H 4 1 for the function class S s ∗ associated with the sine function are given.

scholarly journals Certain subclasses of univalent and bi-univalent functions related to shell-like curves connected with Fibonacci numbers

2020 ◽  
Vol 28 (1) ◽  
pp. 125-140
Author(s):  
Gurmeet Singh ◽  
Gagandeep Singh ◽  
Gurcharanjit Singh
Keyword(s):  
Fibonacci Numbers ◽  
Univalent Functions ◽  
Upper Bounds ◽  
Hankel Determinant ◽  
Second Hankel Determinant

AbstractThis paper is concerned with certain subclasses of univalent and bi-univalent functions related to shell-like curves connected with Fibonacci numbers. We find estimates of the initial coefficients |a2| and |a3| for the functions in these classes. Also we investigate upper bounds for the Fekete-Szegö functional and second Hankel determinant for these classes.

scholarly journals Coefficient Bounds of Kamali-Type Starlike Functions Related with a Limacon-Shaped Domain

2021 ◽  
Vol 2021 ◽  
pp. 1-10
Author(s):  
Gangadharan Murugusundaramoorthy ◽  
Ayesha Shakeel ◽  
Marwan Amin Kutbi
Keyword(s):  
Upper Bound ◽  
Starlike Functions ◽  
Hankel Determinant ◽  
Coefficient Bounds ◽  
Initial Coefficient ◽  
Second Hankel Determinant ◽  
Shaped Domain

In this article, we familiarize a subclass of Kamali-type starlike functions connected with limacon domain of bean shape. We examine certain initial coefficient bounds and Fekete-Szegö inequalities for the functions in this class. Analogous results have been acquired for the functions f − 1 and ξ / f ξ and also found the upper bound for the second Hankel determinant a 2 a 4 − a 3 2 .

Coefficient functionals and radius problems of certain starlike functions

2021 ◽  
pp. 2250089
Author(s):  
Adiba Naz ◽  
Sushil Kumar ◽  
V. Ravichandran
Keyword(s):  
Unit Disk ◽  
Half Plane ◽  
Analytic Functions ◽  
Starlike Functions ◽  
Hankel Determinant ◽  
Radius Problems ◽  
Second Hankel Determinant ◽  
The Right ◽  
Inverse Functions

Ma–Minda class (of starlike functions) consists of normalized analytic functions [Formula: see text] defined on the unit disk for which the image of the function [Formula: see text] is contained in some starlike region lying in the right-half plane. In this paper, we obtain the best possible bounds on some initial coefficients for the inverse functions of Ma–Minda starlike functions. Further, the bounds on the Fekete–Szegö functional and the second Hankel determinant are computed for such functions. In addition, some sharp radius estimates are also determined.

scholarly journals Coefficient bounds for certain subclasses of starlike functions

2019 ◽  
Vol 2019 (1) ◽  
Author(s):  
Nak Eun Cho ◽  
Virendra Kumar ◽  
Oh Sang Kwon ◽  
Young Jae Sim
Keyword(s):  
Analytic Function ◽  
Upper Bound ◽  
Starlike Functions ◽  
Sharp Bound ◽  
Hankel Determinant ◽  
Coefficient Bounds ◽  
Second Hankel Determinant

Abstract The conjecture proposed by Raina and Sokòł [Hacet. J. Math. Stat. 44(6):1427–1433 (2015)] for a sharp upper bound on the fourth coefficient has been settled in this manuscript. An example is constructed to show that their conjectures for the bound on the fifth coefficient and the bound related to the second Hankel determinant are false. However, the correct bound for the latter is stated and proved. Further, a sharp bound on the initial coefficients for normalized analytic function f such that $zf'(z)/f(z)\prec \sqrt{1+\lambda z}$ z f ′ ( z ) / f ( z ) ≺ 1 + λ z , $\lambda \in (0, 1]$ λ ∈ ( 0 , 1 ] , have also been obtained, which contain many existing results.

scholarly journals Second Hankel determinant for tilted bi-starlike functions of order β

2021 ◽  
Vol 1770 (1) ◽  
pp. 012002
Author(s):  
Shaharuddin Cik Soh ◽  
Zammariyah Mustafa Kamal ◽  
Mohamad Huzaifah Mohd Dzubaidi ◽  
Noor Latiffah Adam
Keyword(s):  
Starlike Functions ◽  
Hankel Determinant ◽  
Second Hankel Determinant

SECOND HANKEL DETERMINANT OF LOGARITHMIC COEFFICIENTS OF CONVEX AND STARLIKE FUNCTIONS

2021 ◽  
pp. 1-10
Author(s):  
BOGUMIŁA KOWALCZYK ◽  
ADAM LECKO
Keyword(s):  
Univalent Functions ◽  
Starlike Functions ◽  
Hankel Determinant ◽  
Hankel Matrices ◽  
Sharp Bounds ◽  
Second Hankel Determinant ◽  
Logarithmic Coefficients ◽  
Convex And Starlike Functions

Abstract We begin the study of Hankel matrices whose entries are logarithmic coefficients of univalent functions and give sharp bounds for the second Hankel determinant of logarithmic coefficients of convex and starlike functions.

Sign in / Sign up

Export Citation Format

Share Document