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Journals / Hacettepe Journal of Mathematics and Statistics / 2019 / Cilt: 48 - Sayı: 2

Coefficient estimates for m-fold symmetric bi-subordinate functions

Ebrahim A. Adegani
Samaneh G. Hamidi
Jay M. Jahangiri
Ahmad Zireh
Pages
365–371
Publication Date
2022-10-18
DOI
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AI Summary & Key Takeaways

AI Insight
⚡ TL;DR(Too Long; Didn't Read)

We also determine bounds for the first two coefficients of such functions with no restrictions imposed.

📌 3 Key Takeaways

🎯
Objective & Hypothesis:A function is said to be bi-univalent in the open unit disk U if both the function and its inverse map are univalent in U.
📊
Key Findings & Data:In this paper, we consider the m-fold symmtric transform of such functions and use their Faber polynomial expansions to find upper bounds for their n-th (n ≥ 3) coefficients subject to a given gap series condition.
💡
Conclusion & Impact:We also determine bounds for the first two coefficients of such functions with no restrictions imposed.
🔬Design:Research Article
📍Scope:Comprehensive Sample
⚙️Variables:Domain Parameters

Abstract

A function is said to be bi-univalent in the open unit disk U if both the function and its inverse map are univalent in U. By the same token, a function is said to be bisubordinate in U if both the function and its inverse map are subordinate to a given function in U. In this paper, we consider the m-fold symmtric transform of such functions and use their Faber polynomial expansions to find upper bounds for their n-th (n ≥ 3) coefficients subject to a given gap series condition. We also determine bounds for the first two coefficients of such functions with no restrictions imposed.

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Cite This Article

Adegani, E. A., Hamidi, S. G., Jahangiri, J. M., Zireh, A. (2022). Coefficient estimates for m-fold symmetric bi-subordinate functions. Hacettepe Journal of Mathematics and Statistics, Cilt: 48 - Sayı: 2, 365–371. https://ajindex.com/articles/529778

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