Abstract
Let f(z) be meromorphic in \({\varDelta }\), \(E_1=\{a_1, a_2, a_3\}\) and \(E_2=\{b_1, b_2, b_3\}\) be two sets in \({\mathbb {C}}\), \(k\in Z^+\). Suppose that \(f (z)\in E_1 \Leftrightarrow f^{(k)}(z) \in E_2\) and \(\max \limits _{0\le i\le k-1}|f^{(i)}(z)|=0\) whenever \(f (z)\in E_1\), then f(z) is a normal function.
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References
Hayman, W., Storvick, D.: On normal functions. Bull. Lond. Math. Soc. 3(2), 193–194 (1971)
Hayman, W.K.: Meromorphic functions, vol. 78. Oxford Clarendon Press, Oxford (1964)
Le, Y.: Value distribution theory. Springer, Berlin (1993)
Lehto, O., Virtanen, K.I.: Boundary behaviour and normal meromorphic functions. Acta Math. 97(1), 47–65 (1957)
Liu, X., Pang, X.: Shared values and normal families. Acta Math. Sin. Chin. Ser. 50(2), 409–412 (2007)
Lohwater, A., Pommerenke, C.: On normal meromorphic functions. Ann. Acad. Sci. Fenn. Ser. A1-Math. 550, 1–12 (1973)
Pang, X., Zalcman, L.: Normal families and shared values. Bull. Lond. Math. Soc. 32(3), 325–331 (2000)
Schwick, W.: Sharing values and normality. Arch. Math. 59(1), 50–54 (1992)
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We thank the referee for his/her valuable comments and suggestions made to this paper. This work is partially supported by the National Natural Science Foundation of China (11501367, 61673257), the Natural Science Foundation of Shanghai (17ZR1419900)
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This work is partially supported by the National Natural Science Foundation of China (11501367, 61673257), the Natural Science Foundation of Shanghai (17ZR1419900).
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Chen, Q., Tong, D. Normal functions concerning derivatives and shared sets. Bol. Soc. Mat. Mex. 25, 589–596 (2019). https://doi.org/10.1007/s40590-018-0210-1
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DOI: https://doi.org/10.1007/s40590-018-0210-1