We give sharp coefficient bounds for starlike and convex functions related to modified sigmoid functions. We also provide some sharp coefficient bounds for the inverse functions and sharp bounds for the initial logarithmic coefficients and some coefficient differences.
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Published in Ukrains’kyi Matematychnyi Zhurnal, Vol. 74, No. 5, pp. 683–697, May, 2023. Ukrainian DOI: https://doi.org/10.37863/umzh.v75i5.7093.
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Raza, M., Thomas, D.K. & Riaz, A. Coefficient Estimates for Starlike and Convex Functions Related to Sigmoid Functions. Ukr Math J 75, 782–799 (2023). https://doi.org/10.1007/s11253-023-02228-0
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DOI: https://doi.org/10.1007/s11253-023-02228-0