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arXiv · 2508.09548

Meromorphic functions that partially share values with their first derivative

Andreas Sauer·Andreas Schweizer
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Abstract

We consider uniqueness results for meromorphic functions $f:{\mathbb C} \to \widehat{\mathbb C}$ such that for certain values $a\in {\mathbb C}$ the implication $f(z)=a \Rightarrow f'(z)=a$ holds, i.e. that $f$ and $f'$ share values {\it partially}. In particular, we give a result for four partially shared values.

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Andreas Sauer, Andreas Schweizer. 2025-08-13. Meromorphic functions that partially share values with their first derivative. https://doi.org/10.1007/s00025-026-02624-5

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