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arXiv · 2605.14776

The sharp refined Bohr inequalities for a subclass of close-to-convex harmonic mappings

Ayush Kumar
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Abstract

Let $\mathcal{H}$ be the class of normalized complex valued harmonic functions $ f = h + \overline{g}$ defined on the unit disk $\mathbb{D}$, where $h$ and $g$ are analytic functions with the normalization conditions $h(0) = h'(0) - 1 = 0$ and $g(0) = 0$. For the class $R_H^{0}(γ, δ, λ)$ ( $0 \leq λ< γ\leq δ$) consisting of functions \( f = h+\bar{g} \in \mathcal{H}\) satisfying the condition $f_{\overline{z}}(0)=0$ and the inequality $ Re(γh'(z)+δz h''(z) +(\frac{δ- γ}{2})z^2 h'''(z)-λ)> |γg'(z)+δz g''(z) +(\frac{δ- γ}{2})z^2 g'''(z)|$, we obtain sharp improved Bohr Phenomenon, refined Bohr radius and the Bohr-Rogosinski inequality for the class $R_H^{0}(γ, δ, λ)$.

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Ayush Kumar. 2026-05-14. The sharp refined Bohr inequalities for a subclass of close-to-convex harmonic mappings. https://arxiv.org/abs/2605.14776

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