On Bohr phenomenon for a class of bounded analytic and harmonic functions

Ismaila Amusa; Adesanmi Mogbademu

On Bohr phenomenon for a class of bounded analytic and harmonic functions

Abstract

In this paper, we consider a class of bounded analytic functions f(z)= \sum\limits_{n=0}^{\infty}a_nz^n in the open unit disk, subject to the coefficient bound |a_n| \le 1- |a_0|, n \ge 1. We study functions formed through compositions with Schwarz functions and derive the corresponding Bohr-type bounds. Our investigation also includes sense-preserving harmonic mappings f(z) = h(z) + \overline{g(z)}, where h(z) belongs to the considered analytic class and g'(0)=0. These findings contribute to the improvements and generalizations of some existing results in the literature.

Keywords

References

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Details

Primary Language

English

Subjects

Pure Mathematics (Other)

Journal Section

Research Article

Authors

Ismaila Amusa ^*
0009-0003-0680-4958
Nigeria

Adesanmi Mogbademu
0000-0002-9978-2043
Nigeria

Publication Date

November 28, 2025

Submission Date

August 11, 2025

Acceptance Date

September 19, 2025

Published in Issue

Year 2025 Volume: 1 Number: 1

IZ

https://izlik.org/JA56JP42BE

Cite

RIS / Bibtex

APA

Amusa, I., & Mogbademu, A. (2025). On Bohr phenomenon for a class of bounded analytic and harmonic functions. Düzce Mathematical Research, 1(1), 22-33. https://izlik.org/JA56JP42BE

AMA

1.Amusa I, Mogbademu A. On Bohr phenomenon for a class of bounded analytic and harmonic functions. Düzce Mathematical Research. 2025;1(1):22-33. https://izlik.org/JA56JP42BE

Chicago

Amusa, Ismaila, and Adesanmi Mogbademu. 2025. “On Bohr Phenomenon for a Class of Bounded Analytic and Harmonic Functions”. Düzce Mathematical Research 1 (1): 22-33. https://izlik.org/JA56JP42BE.

EndNote

Amusa I, Mogbademu A (November 1, 2025) On Bohr phenomenon for a class of bounded analytic and harmonic functions. Düzce Mathematical Research 1 1 22–33.

IEEE

[1]I. Amusa and A. Mogbademu, “On Bohr phenomenon for a class of bounded analytic and harmonic functions”, Düzce Mathematical Research, vol. 1, no. 1, pp. 22–33, Nov. 2025, [Online]. Available: https://izlik.org/JA56JP42BE

ISNAD

Amusa, Ismaila - Mogbademu, Adesanmi. “On Bohr Phenomenon for a Class of Bounded Analytic and Harmonic Functions”. Düzce Mathematical Research 1/1 (November 1, 2025): 22-33. https://izlik.org/JA56JP42BE.

JAMA

1.Amusa I, Mogbademu A. On Bohr phenomenon for a class of bounded analytic and harmonic functions. Düzce Mathematical Research. 2025;1:22–33.

MLA

Amusa, Ismaila, and Adesanmi Mogbademu. “On Bohr Phenomenon for a Class of Bounded Analytic and Harmonic Functions”. Düzce Mathematical Research, vol. 1, no. 1, Nov. 2025, pp. 22-33, https://izlik.org/JA56JP42BE.

Vancouver

1.Ismaila Amusa, Adesanmi Mogbademu. On Bohr phenomenon for a class of bounded analytic and harmonic functions. Düzce Mathematical Research [Internet]. 2025 Nov. 1;1(1):22-33. Available from: https://izlik.org/JA56JP42BE