International Journal of Mathematics and Mathematical Sciences
Volume 12 (1989), Issue 1, Pages 199-204
doi:10.1155/S0161171289000244
Notes on certain class of analytic functions with negative coefficients
Shigeyoshi Owa1
, Tadayuki Sekine2
, Teruo Yaguchi3
, Mamoru Nunokawa4
and Donka Pashkouleva5
1Department of Mathematics, Kinki University, Higashi-Osaka, Osaka 577, Japan
2Department of Mathemtics, College of Science and Technology, Nihon University, Kanda-Surugadai, Chiyoda, Tokyo 101, Japan
3Department of Mathematics, College of Humanities and Sciences, Nihon University, Sakurajosui, Setagaya, Tokyo 156, Japan
4Department of Mathematics, Gunma University, Aramaki, Maebashi 371, Japan
5Institute of Mathematics with Computer Center, Bulgarian Academy of Sciences, Sofia 1090, Bulgaria
Abstract
The object of the present paper is to show the extreme points of the class $A(n,B_{k})$ consisting of analytic functions with negative coefficients and the support points of the subclass A _{*}(n,Bk) of $A(n,B_{k})$.