Newman-Rivlin asymptotics for partial sums of power series

Antonio R. Vargas

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arXiv · 1503.04262

Newman-Rivlin asymptotics for partial sums of power series

Antonio R. Vargas

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Abstract

We discuss analogues of Newman and Rivlin's formula concerning the ratio of a partial sum of a power series to its limit function and present a new general result of this type for entire functions with a certain asymptotic character. The main tool used in the proof is a Riemann-Hilbert formulation for the partial sums introduced by Kriecherbauer et al. This new result makes some progress on verifying a part of the Saff-Varga Width Conjecture concerning the zero-free regions of these partial sums.

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Antonio R. Vargas. 2015-03-14. Newman-Rivlin asymptotics for partial sums of power series. https://arxiv.org/abs/1503.04262

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