Abstract
We extend the results on the uniform convergence of Bieberbach polynomials for domains with certain interior zero angles (outward pointing cusps) and show that they play a special role in the problem. Namely, we construct a Keldysh-type example on the divergence of Bieberbach polynomials at an outward pointing cusp and discuss thecritical order of tangency at this interior zero angle, separating the convergent behavior of Bieberbach polynomials from the divergent one for sufficiently thin cusps.
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Research of both authors was supported in part by the National Science Foundation grant DMS-9707359. Research of the second author was also supported in part by the National Science Foundation grant DMS-9970659.
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Andrievskii, V.V., Pritsker, I.E. Convergence of Bieberbach polynomials in domains with interior cusps. J. Anal. Math. 82, 315–332 (2000). https://doi.org/10.1007/BF02791232
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DOI: https://doi.org/10.1007/BF02791232