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Logarithmic Coefficients for Classes Related to Convex Functions

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Abstract

In this work, we estimate the bounds for the logarithmic coefficients \(\gamma _n\) of some well-known classes like \({\mathcal {F}}(c)\) for \(c\in (0,0.656]\cup \{2\}\). The best bound obtained for the logarithmic coefficient \(|\gamma _5|\) is sharp for \(c=2\). In a special case, it is important to note that we obtain the bounds for the logarithmic coefficients \(\gamma _n\) of the convex functions of order \(\alpha \) for some \(\alpha \). It is worthwhile mentioning that the given bounds would generalize some of the previous papers.

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Correspondence to Davood Alimohammadi.

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Communicated by V. Ravichandran.

Dedicated to the memory of Professor Gabriela Kohr (1967-2020)

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The fourth author was supported by the Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science and Technology (No. 2019R1I1A3A01050861).

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Alimohammadi, D., Analouei Adegani, E., Bulboacă, T. et al. Logarithmic Coefficients for Classes Related to Convex Functions. Bull. Malays. Math. Sci. Soc. 44, 2659–2673 (2021). https://doi.org/10.1007/s40840-021-01085-z

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