Some Subclasses of Univalent and Bi-Univalent Functions Related to K-Fibonacci Numbers and Modified Sigmoid Function
DOI:
https://doi.org/10.21123/bsj.2022.6888Keywords:
Bi-univalent function, Borel distribution, Fibonacci numbers, Modified sigmoid function, Univalent functionAbstract
This paper is interested in certain subclasses of univalent and bi-univalent functions concerning to shell- like curves connected with k-Fibonacci numbers involving modified Sigmoid activation function θ(t)=2/(1+e^(-t) ) ,t ≥0 in unit disk |z|<1 . For estimating of the initial coefficients |c_2 | , |c_3 |, Fekete-Szego ̈ inequality and the second Hankel determinant have been investigated for the functions in our classes.
Received 31/12/2021
Accepted 17/5/2022
Published Online First 20/11/2022
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