On the iterated exponent of convergence of zeros of f ( j ) ( z ) − φ ( z )
Tóm tắt
In this paper, the authors investigate the iterated exponent of convergence of zeros of
(
), where f is a solution of some second-order linear differential equation,
is an entire function satisfying
or
(
). We obtain some results which improve and generalize some previous results in (Chen in Acta Math. Sci. Ser. A 20(3):425-432, 2000; Chen and Shon in Chin. Ann. Math. Ser. A 27(4):431-442, 2006; Tu et al. in Electron. J. Qual. Theory Differ. Equ. 23:1-17, 2011) and provide us with a method to investigate the iterated exponent of convergence of zeros of
(
). MSC:34A20, 30D35.
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