English

Sharp bounds of Hankel determinants of second and third order for inverse functions of certain class of univalent functions

Complex Variables 2021-11-22 v3

Abstract

Let A{\mathcal A} be the class of functions that are analytic in the unit disc D{\mathbb D}, normalized such that f(z)=z+n=2anznf(z)=z+\sum_{n=2}^\infty a_nz^n, and let class U(λ){\mathcal U}(\lambda), 0<λ10<\lambda\le1, consists of functions fAf\in{\mathcal A}, such that (zf(z))2f(z)1<λ(zD). \left |\left (\frac{z}{f(z)} \right )^{2}f'(z)-1\right | < \lambda\quad (z\in {\mathbb D}). In this paper we determine the sharp upper bounds for the Hankel determinants of second and third order for the inverse functions of functions from the class U(λ){\mathcal U}(\lambda).

Keywords

Cite

@article{arxiv.2104.01204,
  title  = {Sharp bounds of Hankel determinants of second and third order for inverse functions of certain class of univalent functions},
  author = {Milutin Obradović and Nikola Tuneski},
  journal= {arXiv preprint arXiv:2104.01204},
  year   = {2021}
}