HANKEL DETERMINANT ASSOCIATED WITH LOGISTIC SIGMOID FUNCTIONS IN THE SPACE OF λ-PSEUDO-STARLIKE FUNCTIONS
J. O. HAMZAT *
Department of Pure and Applied Mathematics, Ladoke Akintola University of Technology, P.M.B. 4000, Ogbomoso, Oyo State, Nigeria.
M. T. RAJI
Department of Mathematics and Statistics, The Oke-Ogun Polytechnic, Saki, Oyo State, Nigeria.
A. A. ONI
Department of Pure and Applied Mathematics, Ladoke Akintola University of Technology, P.M.B. 4000, Ogbomoso, Oyo State, Nigeria.
*Author to whom correspondence should be addressed.
Abstract
The present paper is targeted at obtaining the sharp upper bounds for functions belonging to the class 
L λ (α, Ø) of logistic type. The application of these bounds to the Fekete-Szego functional |
a3-μa22 | and the second Hankel determinant 
|a2a4-a23 | were critically examined.
Keywords: Univalent, analytic function, λ - pseudo-starlike function, second Hankel determinant, sigmoid function