Test Starlike Functions for Approximation by Subordinate Polynomials
نویسندگان
چکیده
1 Presented by We construct a function f (z), univalent and starlike in the unit disc, with some interesting geometric and analytic properties. It turns out that its convolutions f * λn with a specific class of univalent polynomials λn(z) are not subordinate to the function itself. This provides a counterexample to a result of Greiner and Ruscheweyh.
منابع مشابه
Applications of subordination theory to starlike functions
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