Fekete–Szegö problem for certain subclasses of analytic functions defined by the combination of differential operators

In this paper, we introduce and study some new subclasses of analytic functions defined by the combination of Al-Oboudi and Ruscheweyh differential operators, and obtain coefficient estimates and Fekete–Szego inequalities for these new subclasses. The results presented in this paper improve the recent work of Kanas and Darwish (Appl Math Lett 23(7), 777–782, 2010).