Some generalization properties of analytic functions concerned with Sakaguchi result


  • Janusz Sokol
  • Mamoru Nunokawa
  • Shigeyoshi Owa
  • Kazuo Kuroki



analytic functions, starlike functions, univalent functions


A subclass $\mathcal{A}(n,k)$ of analytic functions $f(z)$ in the unit disc $\mathbb{U}$ is considered. By means of the result due to K. Sakaguchi (J. Math. Soc. Japan {\bf 11}(1959), 72 -- 75) for $f(z) \in \mathcal{A}(1,1)$, some generalization properties of $f(z) \in \mathcal{A}(n,k)$ with several applications are discussed.

Author Biographies

Janusz Sokol

Department of Mathematics, Rzeszów University of Technology, Al. Powsta´nców Warszawy 12, 35-959 Rzeszów, Poland.

Mamoru Nunokawa

Emeritus Professor, University of Gunma, Hoshikuki-cho 798-8, Chuou-Ward, Chiba, 260-0808, Japan.

Shigeyoshi Owa

Department of Mathematics, Faculty of Education, Yamato University, Katayama 2-5-1, Suita, Osaka 564-0082,Japan.

Kazuo Kuroki

Department ofMathematics, Kinki University, Higashi-Osaka, Osaka 577-8502, Japan.


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How to Cite

Sokol, J., Nunokawa, M., Owa, S., & Kuroki, K. (2015). Some generalization properties of analytic functions concerned with Sakaguchi result. Tamkang Journal of Mathematics, 46(2), 143-150.