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arXiv · 1611.01267

A normality criterion corresponding to the defect relations

Andreas Schweizer
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Abstract

Let ${\cal F}$ be a family of meromorphic functions on a domain $D$. We present a quite general sufficient condition for ${\cal F}$ to be a normal family. This criterion contains many known results as special cases. The overall idea is that certain comparatively weak conditions on ${\cal F}$ locally lead to somewhat stronger conditions, which in turn lead to even stronger conditions on the limit function $g$ in the famous Zalcman Lemma. Ultimately, the defect relations for $g$ force normality of ${\cal F}$.

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Andreas Schweizer. 2016-11-04. A normality criterion corresponding to the defect relations. https://doi.org/10.1007/s40315-017-0196-0

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