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Keywords:
analytic; subordination; Fekete–Szegö problem
Summary:
In this paper, we obtain Fekete–Szegö inequalities for a generalized class of analytic functions $f(z)\in \mathcal {A} $ for which $1+\frac{1}{b}\Big ( \frac{z\left( D_{\alpha ,\beta ,\lambda ,\delta }^n f(z)\right)^{\prime }}{D_{\alpha ,\beta ,\lambda ,\delta }^{n}f(z)}-1\Big )$ ($\alpha ,\beta ,\lambda ,\delta \ge 0$; $\beta >\alpha $; $\lambda >\delta $; $b\in \mathbb {C}^{\ast }$; $n\in \mathbb {N}_{0}$; $z\in U$) lies in a region starlike with respect to $1$ and is symmetric with respect to the real axis.
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