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arXiv · 2607.12509

On Hankel Determinants of $\beta$-Spirallike Mappings in Complex Banach Spaces

Nabadwip Sarkar·Pradip Das
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Abstract

This paper is devoted to the study of the second Hankel determinant for normalized $\beta$-spirallike mappings on the unit ball of a complex Banach space. Using the relationship between Banach-space holomorphic mappings and corresponding one-variable $\beta$-spirallike functions, we first establish sharp estimates for the initial homogeneous expansion coefficients. These coefficient inequalities are subsequently applied to derive a sharp bound for the second Hankel determinant.

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Nabadwip Sarkar, Pradip Das. 2026-07-14. On Hankel Determinants of $\beta$-Spirallike Mappings in Complex Banach Spaces. https://arxiv.org/abs/2607.12509

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