Fourth Hankel Determinant for a Subclass of Starlike Functions Based on Modified Sigmoid. (16th December 2021)

• Record Type: Journal Article
• Authors: Mashwani, Wali Khan; Ahmad, Bakhtiar; Khan, Nazar; Khan, Muhammad Ghaffar; Arjika, Sama; Khan, Bilal; Chinram, Ronnason
• Other Names: Akeroyd John R. Academic Editor.
• Is Part Of: Journal of function spaces. Volume 2021(2021)
• Publication Date: 2021-12-16
• Subjects: Function spaces -- Periodicals; 515.7305
• DOI: 10.1155/2021/6116172
• Languages: English
• ISSNs: 2314-8896

Abstract

Abstract : In our present investigation, we obtain the improved third-order Hankel determinant for a class of starlike functions connected with modified sigmoid functions. Further, we investigate the fourth-order Hankel determinant, Zalcman conjecture, and also evaluate the fourth-order Hankel determinants for 2-fold, 3-fold, and 4-fold symmetric starlike functions.