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arXiv · 1207.5214

On the spherical derivative of a rational function

Matthew Barrett·Alexandre Eremenko
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Abstract

For a rational function f we consider the norm of the derivative with respect to the spherical metric and denote by K(f) the supremum of this norm. We give estimates of this quantity K(f) both for an individual function and for sequences of iterates.

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Matthew Barrett, Alexandre Eremenko. 2012-07-22. On the spherical derivative of a rational function. https://arxiv.org/abs/1207.5214

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