Abstract
In this paper, we study one conjecture proposed by W. Bergweiler and show that any transcendental meromorphic functions f(z) have the form exp(αz+β) if f(z)f″(z)–a(f′ (z))2≠0, where \( a \ne 1,\;\frac{{n \pm 1}} {n},\;n \in N \). Moreover, an analogous normality criterion is obtained.
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Hayman, W. K.: Picard values of meromorphic functions and their derivatives. Ann. of Math., 70, 9–42 (1959)
Muse, E.: Uber eine Vermutung von Hayman. Math. Z., 119, 11–20 (1971)
Langley, J. K.: Proof of a conjecture of Hayman concerning f and f". J. London Math. Soc., 48(2), 500–514 (1993)
Muse, E.: Ueber dic Nullstellen homogener differetial Polynome. Manuscripta Math., 23, 325–341 (1978)
Bergweiler, B.: On the zeros of certain homogeneous differential polynomials. Arch. Math., 64, 199–202 (1995)
Langley, J. K.: On differential polynomials, fixpoints and critical values of meromorphic functions. Result. Math., 35, 284–309 (1999)
Gu, Y. X.: On normal families of holomorphic functions. Acta Math. Sinica, Chinese Series, 23, 157–161 (1980)
Bergweiler, W.: Normality and exceptional values of derivatives. Proc. Amer. Math. Soc., 129(1), 121–129 (2000)
Bergweiler, W., Eremenko, A.: On the singularities of the inverse to a meromorphic function of finite order. Rev. Mat. Iberoam, 11, 355–373 (1995)
Rippon, P. J., Stallard, G. M.: Iteration of a class of hyperbolic meromorphic functions. Proc. Amer. Math. Soc., 115(2), 355–362 (1999)
Wang, Y. F., Fang, M. L.: Picard values and normal families of meromorphic functions with multiple zeros. Acta Math. Sinica, Chinese Series, 41, 743–748 (1998)
Pang, X. C., Zalcman, L.: Normal families and shared values. Bull. London Math. Soc., 32, 325–331 (2000)
Yang, L.: Value Distribution Theory, Springer–Verlag, Berlin–Heidelberg, 1993
Hayman, W. K.: Meromorphic Functions, Clarendon, Oxford, 1964
Zalcman, L.: Normal families: new perspectives. Bull. Amer. Math. Soc. New Ser., 35, 215–230 (1998)
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Supported by National Natural Science Foundation and Science Technology Promotion Foundation of Fujian Province (2003)
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Lin, W.C., Yi, H.X. On Homogeneous Differential Polynomials of Meromorphic Functions. Acta Math Sinica 21, 261–266 (2005). https://doi.org/10.1007/s10114-004-0326-2
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DOI: https://doi.org/10.1007/s10114-004-0326-2