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Coefficient inequality for parabolic starlike functions of order alpha

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Abstract

The aim of this paper is to obtain a sharp upper bound to the second Hankel determinant \(|a_{2}a_{4}-a_{3}^{2}|\) for the function \(f\) when it belongs to the class of parabolic starlike functions of order \(\alpha (0\le \alpha <1).\) Further, an upper bound for the inverse function of \(f\) to the non-linear functional \(|t_{2}t_{4}-t_{3}^{2}|\) was determined when it belongs to the same class of functions, using Toeplitz determinants.

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Acknowledgments

The authors would like to express their sincere thanks to the esteemed Referee(s) for their careful readings, valuable suggestions and comments, which helped to improve the presentation of the paper.

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Correspondence to D. Vamshee Krishna.

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Vamshee Krishna, D., RamReddy, T. Coefficient inequality for parabolic starlike functions of order alpha. Afr. Mat. 27, 121–132 (2016). https://doi.org/10.1007/s13370-015-0322-y

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  • DOI: https://doi.org/10.1007/s13370-015-0322-y

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