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Inverse Polynomial Images are Always Sets of Minimal Logarithmic Capacity

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Abstract

In this paper, we prove that each inverse polynomial image (that is, each inverse image of an interval with respect to a polynomial mapping) is a set of minimal logarithmic capacity in a certain sense. Such sets play an important role in the theory of Padé-Approximation. The proofs are all based on the characterization theorems of Herbert Stahl.

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Acknowledgments

The author would like to thank the referee for pointing out an error in an earlier version of the paper and for several important suggestions.

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Correspondence to Klaus Schiefermayr.

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Communicated by Stephan Ruscheweyh.

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Schiefermayr, K. Inverse Polynomial Images are Always Sets of Minimal Logarithmic Capacity. Comput. Methods Funct. Theory 16, 375–386 (2016). https://doi.org/10.1007/s40315-015-0143-x

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  • DOI: https://doi.org/10.1007/s40315-015-0143-x

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