Hankel determinant of second order for some classes of analytic functions

Milutin Obradovic; Nikola Tuneski

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arXiv · 1903.08069

Hankel determinant of second order for some classes of analytic functions

Milutin Obradovic·Nikola Tuneski

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Abstract

Let $f$ be analytic 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 upper bounds of the Hankel determinant of second order for the classes of starlike functions of order $\alpha$, Ozaki close-to-convex functions and two other classes of analytic functions. Some of the estimates are sharp.

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Milutin Obradovic, Nikola Tuneski. 2019-03-19. Hankel determinant of second order for some classes of analytic functions. https://arxiv.org/abs/1903.08069

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