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The Sharp Bound of the Fifth Coefficient of Strongly Starlike Functions with Real Coefficients

  • Oh Sang Kwon
  • Adam Lecko
  • Young Jae SimEmail author
  • Barbara Śmiarowska
Article
  • 49 Downloads

Abstract

In this paper, we found the sharp bound of the fifth coefficient of strongly starlike functions of order \(\alpha \) with real coefficients for all \(\alpha \in (0,1]\).

Keywords

Strongly starlike functions Carathéodory functions Schwarz functions Coefficient estimates 

Mathematics Subject Classification

30C45 30C50 

Notes

Acknowledgements

The authors thank the referees for their careful reading and useful comments. This work was partially supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIP; Ministry of Science, ICT and Future Planning) (No. NRF-2017R1C1B5076778).

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Copyright information

© Malaysian Mathematical Sciences Society and Penerbit Universiti Sains Malaysia 2018

Authors and Affiliations

  1. 1.Department of MathematicsKyungsung UniversityBusanKorea
  2. 2.Department of Complex AnalysisUniversity of Warmia and Mazury in OlsztynOlsztynPoland

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