Honam Mathematical Journal (호남수학학술지)

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BOUND ON HANKEL DETERMINANTS H(2)4 (f) AND H(3)4 (f) FOR LEMNISCATE STARLIKE FUNCTIONS

  • Sushil Kumar (Department of Applied Sciences, Bharati Vidyapeeth's College of Engineering) ;
  • Pratima Rai (Department of Mathematics, University of Delhi) ;
  • Asena Cetinkaya (Department of Mathematics and Computer Science, Istanbul Kultur University)
  • Received : 2022.06.10
  • Accepted : 2022.11.17
  • Published : 2023.03.25
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Abstract

We determine the upper bounds on fourth order Hankel determinants H(2)4(f) and H(3)4(f) for the class S*L of lemniscate starlike functions defined on the open unit disk which was introduced by Sokół and Stankiewicz in [17].

Keywords

Acknowledgement

The authors Sushil Kumar and Pratima Rai would like to thank the Institute of Eminence, University of Delhi, Delhi, India-110007 for providing financial support for this research under grant number /IoE/2021/12/FRP.

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