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The logarithmic derivative of a meromorphic function

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Abstract

A well-known lemma on the logarithmic derivative for a function f(z), f(0) = 1 (0 < r <ϱ<R), meromorphic in {¦z¦<R ≤ ∞ is proved in the following form:

$$m\left( {r,\frac{{f'}}{f}} \right)< \ln + \left\{ {\frac{{T(\rho ,f)}}{r}\frac{\rho }{{\rho - r}}} \right\} + 5.8501.$$

. This estimate is more exact than the one previously obtained by Kolokol'nikov and is, in a certain sense, unimprovable.

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Literature cited

  1. A. A. Gol'dberg and I. V. Ostrovskii, Distribution of the Values of Meromorphic Functions [in Russian], Nauka, Moscow (1970).

    Google Scholar 

  2. A. S. Kolokol'nikov, “The logarithmic derivative of a meromorphic function,” Matem. Zametki,15, No. 5, 711–718 (1974).

    Google Scholar 

  3. Vu Ngoan and I. V. Ostrovskii, “The logarithmic derivative of a meromorphic function,” Dokl. Akad. Nauk ArmSSR,41, 272–277 (1965).

    Google Scholar 

  4. M. V. Keldysh, “On series in rational fractions,” Dokl. Akad. Nauk SSSR,94, No. 3, 377–380 (1954).

    Google Scholar 

  5. P. B. Kennedy, “A property of bounded regular functions,” Proc. Roy. Irish Acad., Sect. A,60, No. 2, 7–14 (1959).

    Google Scholar 

  6. R. Nevanlinna, Le Théorème de Picard-Borel et la Théorie des Fonctions Méromorphes, Gauthier-Villars, Paris (1929).

    Google Scholar 

  7. T. Shimizu, K. Yosida, and S. Kakutani, “On meromorphic functions,” Proc. Phys. Math. Soc. Japan,17, No. 1, 1–10 (1935).

    Google Scholar 

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Translated from Matematicheskie Zametki, Vol. 19, No. 4, pp. 525–530, April, 1976.

The authors thank A. S. Kolokol'nikov for discussing this note.

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Gol'dberg, A.A., Grinshtein, V.A. The logarithmic derivative of a meromorphic function. Mathematical Notes of the Academy of Sciences of the USSR 19, 320–323 (1976). https://doi.org/10.1007/BF01156790

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  • DOI: https://doi.org/10.1007/BF01156790

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