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arXiv · 2610.21255

On coefficient theorems for starlike and quasi-convex of type B mappings in complex Banach spaces

Janusz Sokol·Sujoy Majumder·Goutam Haldar
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Abstract

In this paper, we study biholomorphic mappings $F: \mathbb{B} \to X$ of the form $F(z) = f(z)z$ for $z \in \mathbb{B}$, where $f: \mathbb{B} \to \mathbb{C}$ is a holomorphic function satisfying $f(0) = 1$ and $X$ is a complex Banach space with the unit ball $\mathbb{B}$. The main contributions of this paper are threefold. First, we establish a sufficient coefficient condition for a function $F(z)=zf(z)$ to be starlike and quasi-convex of type $B$ in a complex Banach space. Second, we prove that the Bieberbach conjecture holds for these classes of functions. Finally, we analyze the difference of coefficients for such functions in this setting. The results established here directly extend the previous results to the broader setting of complex Banach spaces.

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Janusz Sokol, Sujoy Majumder, Goutam Haldar. 2026-10-15. On coefficient theorems for starlike and quasi-convex of type B mappings in complex Banach spaces. https://arxiv.org/abs/2610.21255

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