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Improved Bohr radius for $ k$-fold symmetric univalent logharmonic mappings

Complex Variables 2023-08-15 v1

Abstract

We study the kk-fold symmetric starlike univalent logharmonic mappings of the form f(z)=zh(z)g(z)f(z)=zh(z)\overline{g(z)} in the unit disk D:={zC:z<1}\mathbb{D}:= \lbrace z \in \mathbb{C}: |z|<1 \rbrace with several examples, where h(z)=exp(n=1ankznk)h(z)=\exp \left(\sum_{n=1}^{\infty}a_{nk}z^{nk}\right) and g(z)=exp(n=1bnkznk)g(z)=\exp \left(\sum_{n=1}^{\infty}b_{nk}z^{nk}\right) are analytic in D.\mathbb{D}. The distortion bounds of these functions are obtained, which give area bounds. Improved Bohr radii for this family are calculated. We also introduce the pre-Schwarzian and Schwarzian derivatives of logharmonic mappings that vanish at the origin.

Keywords

Cite

@article{arxiv.2308.06476,
  title  = {Improved Bohr radius for $ k$-fold symmetric univalent logharmonic mappings},
  author = {Akash Meher and Priyabrat Gochhayat},
  journal= {arXiv preprint arXiv:2308.06476},
  year   = {2023}
}