Science China Mathematics

, Volume 53, Issue 3, pp 739–748 | Cite as

Real meromorphic functions and linear differential polynomials

Articles
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Abstract

We determine all real meromorphic functions f in the plane such that f′ has finitely many zeros, the poles of f have bounded multiplicities, and f and F have finitely many non-real zeros, where F is a linear differential polynomial given by F = f (k)+Σ j=0 k−1 α j f (j) , in which k ⩾ 2 and the coefficients a j are real numbers with a 0 ≠ 0.

Keywords

non-real zeros meromorphic function linear differential polynomial 

MSC(2000)

30D20 30D35 
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Copyright information

© Science China Press and Springer-Verlag Berlin Heidelberg 2010

Authors and Affiliations

  1. 1.School of Mathematical SciencesUniversity of NottinghamNottinghamUK

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