English

Logarithmic Coefficients Problems of Geometric Subclass of Closed-to-convex Functions

Complex Variables 2026-05-20 v1

Abstract

For α0\alpha\ge 0, let W(α)\mathcal{W}(\alpha) be the class of all analytic functions in the unit disk D\mathbb{D} with normalization f(0)=0f(0) = 0 and f(0)=1 f'(0) = 1 that satisfy the relation Re{f(z)+αzf(z)}>0Re\,\{f'(z) + \alpha z f''(z)\} > 0. This article aims to establish sharp bounds for logarithmic coefficients γ1\gamma_1, γ2\gamma_2 and γ3\gamma_3 and logarithmic inverse coefficients Γ1\Gamma_1, Γ2\Gamma_2 and Γ3\Gamma_3 of functions in W(α)\mathcal{W}(\alpha). The sharp upper and lower bounds for γ2γ1\bigl|\,\gamma_2 \,\bigr|-\bigl|\,\gamma_1\,\bigr| and Γ2Γ1\bigl|\,\Gamma_2 \,\bigr|-\bigl|\,\Gamma_1\,\bigr| have been obtained for the class W(α)\mathcal{W}{(\alpha)}. In addition, we establish sharp inequality for the second Hankel determinant of the logarithmic and inverse logarithmic coefficients for the class W(1)\mathcal{W}{(1)}.

Keywords

Cite

@article{arxiv.2605.20089,
  title  = {Logarithmic Coefficients Problems of Geometric Subclass of Closed-to-convex Functions},
  author = {Chayani Dhara and Nirupam Ghosh},
  journal= {arXiv preprint arXiv:2605.20089},
  year   = {2026}
}