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Volume 46, No. 02, Month FEBRUARY, Year 2020, Pages 227 - 234


Normal families of meromorphic functions which share a set

Jinhua Cai, Fanning Meng, Jia Xie, Wenjun Yuan


Abstract Download PDF

In this paper, by using the Nevanlinna’s value distribution theory and the method of Zalcman-Pang, it investigates the normality of a family of meromorphic functions, denoted by  , defined in a domain D, which concerns the conditions for each ƒ ∈  : (i) E(S1, ƒ ) = E (S2, ( ƒ (k))q); (ii) both zeros and poles of ƒ −a have multiplicities at least k (> 2 or  2) and k + 1, respectively, or k ( 4) and k − 1, respectively, where k and q are positive integers, a is any finite complex number, S1 = {a1, a2, a3} and S2 = {b1, b2, b3} are made up of finite complex numbers. The conclusion still holds if condition (ii) is replaced by the assumption that zeros of ƒ − ai have multiplicities at least k, where k  1 and i = 1, 2, 3.


Keywords

meromorphic functions, normality, shared set



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