^{1}Department of Mathematics, Payame Noor University, P.O.Box 19395-3697, Tehran, Iran.

^{2}Department of Mathematics, Faculty of Science, Arak University, Arak 38156-8-8349, Iran.

Abstract

In the present paper, we introduce and investigate some properties of two subclasses $ \Lambda_{n}( \lambda , \beta ) $ and $ \Lambda_{n}^{+}( \lambda , \beta ) $; meromorphic and starlike functions of order $ \beta $. In particular, several inclusion relations, coefficient estimates, distortion theorems and covering theorems are proven here for each of these function classes.

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