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

Gurmeet Singh; Gagandeep Singh; Gurcharanjit Singh

doi:10.2478/gm-2020-0010

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

General Mathematics

Volume 28 (2020): Issue 1 (June 2020)

By: Gurmeet Singh, Gagandeep Singh and Gurcharanjit Singh

Open Access

|Jul 2020

Abstract

This 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.

References

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Articles in this issue

DOI: https://doi.org/10.2478/gm-2020-0010 | Journal eISSN: 1584-3289 | Journal ISSN: 1221-5023

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Language: English

Page range: 125 - 140

Submitted on: Mar 2, 2019

Accepted on: Jan 29, 2020

Published on: Jul 31, 2020

Published by: Lucian Blaga University of Sibiu

In partnership with: Paradigm Publishing Services

Publication frequency: 2 issues per year

Keywords:

Sãlãgean operator,

bi-univalent functions,

Related subjects:

Differential equations and dynamical systems,

Probability and statistics,

Numerical and computational mathematics,

Applied mathematics

© 2020 Gurmeet Singh, Gagandeep Singh, Gurcharanjit Singh, published by Lucian Blaga University of Sibiu
This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Volume 28 (2020): Issue 1 (June 2020)