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arXiv · 1903.07872

Hankel determinant for a class of analytic functions

Milutin Obradovic·Nikola Tuneski
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Abstract

Let $f$ be analutic in the unit disk $\mathbb D$ and normalized so that $f(z)=z+a_2z^2+a_3z^3+\cdots$. In this paper we give sharp bound of Hankel determinant of the second order for the class of analytic unctions satisfying \[ \left|\arg \left[\left(\frac{z}{f(z)}\right)^{1+α}f'(z) \right] \right|<γ\fracπ{2} \quad\quad (z\in\mathbb D),\] for $0<α<1$ and $0<γ\leq1$.

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Milutin Obradovic, Nikola Tuneski. 2019-03-19. Hankel determinant for a class of analytic functions. https://arxiv.org/abs/1903.07872

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