## Abstract and Applied Analysis

### Normal Families of Zero-Free Meromorphic Functions

Yuntong Li

#### Abstract

Let $a(\ne \mathrm{0}), b\in \Bbb C$, and $n$ and $k$ be two positive integers such that $n\ge 2$. Let $\scr F$ be a family of zero-free meromorphic functions defined in a domain $\mathrm{\scr D}$ such that for each $f\in \scr F$, $f+a{({f}^{(k)})}^{n}-b$ has at most $nk$ zeros, ignoring multiplicity. Then $\scr F$ is normal in $\mathrm{\scr D}$.

#### Article information

Source
Abstr. Appl. Anal., Volume 2012 (2012), Article ID 908123, 12 pages.

Dates
First available in Project Euclid: 14 December 2012

Permanent link to this document
https://projecteuclid.org/euclid.aaa/1355495834

Digital Object Identifier
doi:10.1155/2012/908123

Mathematical Reviews number (MathSciNet)
MR2965459

Zentralblatt MATH identifier
1247.30054

#### Citation

Li, Yuntong. Normal Families of Zero-Free Meromorphic Functions. Abstr. Appl. Anal. 2012 (2012), Article ID 908123, 12 pages. doi:10.1155/2012/908123. https://projecteuclid.org/euclid.aaa/1355495834

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