Document Type : Research Paper

Authors

• Gagandeep Singh ¹
• Gurcharanjit Singh ²

¹ Department of Mathematics, Khalsa College, Amritsar-143001, Punjab, India

² Department of Mathematics, G.N.D.U. College, Chungh-143304, Tarn-Taran(Punjab), India

Abstract

In this paper, we introduce a subclass of analytic functions associated with the Sigmoid function and determine the upper bounds for various coefficient functionals such as  Fekete-Szego functional, second Hankel determinant, Zalcman functional and third Hankel determinant. Also, the concept is extended to two-fold and three-fold symmetric functions. The results proved earlier, follow as special cases of the results of this paper.

Keywords

• Subordination
• Hankel determinant
• Fekete Szego functional
• Zalcman functional