International Journal of Mathematics and Mathematical Sciences 
Volume 2004 (2004), Issue 36, Pages 1937-1942
doi:10.1155/S0161171204309051

Coefficient estimates for Ruscheweyh derivatives

Maslina Darus and Ajab Akbarally

 School of Mathematical Sciences, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, Bangi, Selangor Darul Ehsan 43600, Malaysia
Received 5 September 2003

Abstract

We consider functions f, analytic in the unit disc and of the normalized form f(z)=z+∑n=2∞anzn. For functions f∈R¯δ(β), the class of functions involving the Ruscheweyh derivatives operator, we give sharp upper bounds for the Fekete-Szegö functional |a3−μa22|.