Abstract
Let G ⊂ ℂ be a simply connected domain whose boundary L := ∂G is a Jordan curve and 0 ∈ G. Let w = φ(z) be the conformal mapping of G onto the disk B(0, r 0) := {w : |w| < r 0}, satisfying φ(0) = 0, φ′(0) = 1. We consider the following extremal problem for p > 0:
in the class of all polynomials P n (z) of degree not exceeding n with P n (0) = 0, P n ′ (0) = 1. The solution to this extremal problem is called the p-Bieberbach polynomial of degree n for the pair (G, 0). We study the uniform convergence of the p-Bieberbach polynomials B n,p (z) to the φ(z) on \(\bar G\) with interior and exterior zero angles determined depending on the properties of boundary arcs and the degree of their “touch”.
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Abdullayev, F.G., Özkartepe, P.N. Uniform convergence of the p-Bieberbach polynomials in domains with zero angles. Sci. China Math. 58, 1063–1078 (2015). https://doi.org/10.1007/s11425-014-4908-x
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DOI: https://doi.org/10.1007/s11425-014-4908-x