Simple proofs of certain inequalities with logarithmic coefficients of univalent functions

M. Obradović (University of Belgrade), https://orcid.org/0000-0001-8890-0764
N. Tuneski (Ss. Cyril and Methodius University in Skopje), https://orcid.org/0000-0003-3889-0048

Abstract


In this paper, we give simple proofs for the bounds (some of them sharp) of the difference of the moduli of the second and the first logarithmic coefficient for the general class of univalent functions and for the class of convex univalent functions.

Keywords


univalent functions; convex functions; logarithmic coefficient; moduli; estimate

MSC 2020


Pri 30C45, Sec 30C50

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References


Bieberbach L. "Über die Koeffizienten derjenigen Potenzreihen, welche eine schlichte Abbildung des Einheitskreises vermitteln", Sitzungsber. Preuss. Akad. Wiss. Phys-Math., 1916; 138: pp. 940-955. (in German)

de Branges L. "A proof of the Bieberbach conjecture", Acta Math., 1985; 154(1-2): pp. 137-152. doi:10.1007/BF02392821

Lecko A., Partyka D. "Successive Logarithmic Coefficients of Univalent Functions", Comput. Methods Func. Theory, 2023. doi:10.1007/s40315-023-00500-9

Thomas D.K., Tuneski N., Vasudevarao A. Univalent Functions: A Primer, De Gruyter Studies in Mathematics 69, De Gruyter, 2018.

Trimble S.Y. "A Coefficient Inequality for Convex Univalent Functions", Proc. Amer. Math. Soc., 1975; 48(1): pp. 266-267. doi:10.1090/S0002-9939-1975-0355027-0




DOI: https://doi.org/10.15421/242412

  

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ISSN (Online): 2664-5009
ISSN (Print): 2664-4991
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