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CJPLS: VOL. 13, NO. 1, JUNE 2025

Coefficient bounds for subclass of Sigmoid functions involving subordination principle defined by Salagean Differential Operator

Submitted
January 16, 2025
Published
2025-02-28

Abstract

The authors of this research investigated a subclass analytic univalent function from the perspective of sigmoid functions defined by using the Salagean differential operator and subordination principles. Coefficient constraints were found for this subclass and the well-known Fekete Szego inequalities were also mentioned. Therefore, in addition to the standard Fekete-Szegʝo problem, the relationship between unified subclasses of analytic univalent functions and a simple logistic activation function to find the initial Taylor series coefficients.

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