The zeros of the first two derivatives of a meromorphic function

Langley, J.

doi:10.1090/S0002-9939-96-03350-3

The zeros of the first two derivatives of a meromorphic function
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by J. K. Langley PDF

Proc. Amer. Math. Soc. 124 (1996), 2439-2441 Request permission

Abstract:

We prove a theorem which implies the following: if $f$ is meromorphic of finite order in the plane and $f’$ and $f''$ have only finitely many zeros, then $f$ has only finitely many poles.

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