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arXiv · 2403.19403

Non-real zeros of derivatives in the unit disc

James Langley
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Abstract

The main result establishes an estimate for the growth of a real meromorphic function $f$ on the unit disc $\Delta$ such that: (i) at least one of $f$ and $1/f$ has finitely many poles and non-real zeros in $\Delta$; (ii)~$f^{(k)}$ has finitely many non-real zeros in $\Delta$, for some $k \geq 2$.

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James Langley. 2024-03-28. Non-real zeros of derivatives in the unit disc. https://arxiv.org/abs/2403.19403

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