The zeros of f^{n}f^(k)-a and normal families of meromorphic functions

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sun xiong

Abstract

In this paper, we first prove that if f be a non-constant meromorphic function, all of whose zeros have multiplicity at least $k$, then f^{n}f^{(k)}-a has at least m+1 distinct zeros, where $k(\geq2),m(\geq1),n(\geq m+1)$ are three integers, and $a\in \mathbb{C}\cup\setminus\{0\}$.Also, in relation to this result, a normality criteria is given, which extends the related result.

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How to Cite
xiong, sun. (2020). The zeros of f^{n}f^(k)-a and normal families of meromorphic functions. Tamkang Journal of Mathematics, 51(2), 137–144. https://doi.org/10.5556/j.tkjm.51.2020.3041
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Papers