Radius of starlikeness for the class \(S(\alpha,n)\) (Q1919349)

In this paper the sharp radius of starlikeness is obtained for the family of functions \(f\) that are analytic in the open unit disk, satisfy \(\text{Re} {f(z)\over z} >\alpha\) for \(|z|<1\) \((0\leq \alpha<1)\), and have a power series beginning \(f(z)= z+a_n z^n+a_{n+1} z^{n+1} +\dots (n\geq 2)\). The author obtained an estimate of this radius in [Northeast. Math. 7, No. 1, 27-32 (1991; Zbl 0761.30003)].