A class of univalent functions with real coefficients

Milutin Obradovic; Nikola Tuneski

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arXiv · 1810.03839

A class of univalent functions with real coefficients

Milutin Obradovic·Nikola Tuneski

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Abstract

In this paper we study class $\mathcal{S}^+$ of univalent functions $f$ such that $\frac{z}{f(z)}$ has real and positive coefficients. For such functions we give estimates of the Fekete-Szeg\H{o} functional and sharp estimates of their initial coefficients and logarithmic coefficients. Also, we present necessary and sufficient conditions for $f\in \mathcal{S}^+$ to be starlike of order $1/2$.

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Milutin Obradovic, Nikola Tuneski. 2018-10-09. A class of univalent functions with real coefficients. https://arxiv.org/abs/1810.03839

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