Abstract
In the present paper, we determine necessary and sufficient conditions for zF(a, b; c; z) and \(z(2-F(a,b;c;z))\) where \(F(a,b;c;z)=\sum \nolimits _{n=0}^{\infty }[(a)_{n}(b)_{n}/(c)_{n}(1)_{n}]z^{n}\) to be in a certain class of analytic functions with negative coefficients. Furthermore, we consider an integral operator related to hypergeometric functions.
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The authors would like to thank the referees for their helpful comments and suggestions.
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Frasin, B.A., Al-Hawary, T. & Yousef, F. Necessary and sufficient conditions for hypergeometric functions to be in a subclass of analytic functions. Afr. Mat. 30, 223–230 (2019). https://doi.org/10.1007/s13370-018-0638-5
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DOI: https://doi.org/10.1007/s13370-018-0638-5