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Hankel determinants for starlike and convex functions associated with sigmoid functions

  • Amina Riaz , Mohsan Raza EMAIL logo and Derek K. Thomas
Published/Copyright: December 1, 2021

Abstract

This paper is concerned with Hankel determinants for starlike and convex functions related to modified sigmoid functions. Sharp bounds are given for second and third Hankel determinants.

MSC 2010: 30C45; 30C50

Communicated by Shigeharu Takayama


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Received: 2021-07-22
Revised: 2021-10-18
Published Online: 2021-12-01
Published in Print: 2022-01-01

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