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arXiv · 1709.08944

Improved Bohr's inequality for locally univalent harmonic mappings

Stavros Evdoridis·Saminathan Ponnusamy·Antti Rasila
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Abstract

We prove several improved versions of Bohr's inequality for the harmonic mappings of the form $f=h+\overline{g}$, where $h$ is bounded by 1 and $|g'(z)|\le|h'(z)|$. The improvements are obtained along the lines of an earlier work of Kayumov and Ponnusamy, i.e. \cite{KayPon2}, for example a term related to the area of the image of the disk $D(0,r)$ under the mapping $f$ is considered. Our results are sharp. In addition, further improvements of the main results for certain special classes of harmonic mappings are provided.

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Stavros Evdoridis, Saminathan Ponnusamy, Antti Rasila. 2017-09-26. Improved Bohr's inequality for locally univalent harmonic mappings. https://arxiv.org/abs/1709.08944

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