Computational Methods and Function Theory ( IF 2.1 ) Pub Date : 2020-08-07 , DOI: 10.1007/s40315-020-00337-6 Xiao-Min Li , Yan Liu , Hong-Xun Yi
In 2011, Heittokangas et al. (Complex Var Ellipt Equat 56(1–4):81–92, 2011) proved that if a non-constant finite order entire function f(z) and \(f(z+\eta )\) share a, b, c IM, where \(\eta \) is a finite non-zero complex number, while a, b, c are three distinct finite complex values, then \(f(z)=f(z+\eta )\) for all \(z\in \mathbb {C}\). We prove that if a non-constant finite order entire function f and its n-th difference operator \(\Delta ^n_{\eta }f\) share \(a_1\), \(a_2\), \(a_3\) IM, where n is a positive integer, \(\eta \ne 0\) is a finite complex value, while \(a_1\), \(a_2\), \(a_3\) are three distinct finite complex values, then \(f=\Delta ^n_{\eta }f\). The main results in this paper also improve Theorems 1.1 and 1.2 from Li and Yi (Bull Korean Math Soc 53(4):1213–1235, 2016).
中文翻译:
亚纯函数与其差值运算符共享四个值
2011年,Heittokangas等人。(Complex Var Ellipt Equat 56(1-4):81-92,2011)证明,如果非恒定有限阶整函数f(z)和\(f(z + \ eta)\)共享a,b,c IM,其中\(\ eta \)是一个有限的非零复数,而a,b,c是三个不同的有限复数值,则\(f(z)= f(z + \ eta)\)对于所有\ (z \ in \ mathbb {C} \)。我们证明,如果一个非恒定有限阶完整函数f及其第n个差分算子\(\ Delta ^ n _ {\ eta} f \)共享\(a_1 \),\(a_2 \),\(a_3 \) IM,其中n是正整数,\(\ eta \ ne 0 \)是有限复数,而\(a_1 \),\ (a_2 \),\(a_3 \)是三个不同的有限复数值,然后是\(f = \ Delta ^ n _ {\ eta} f \)。本文的主要结果也改进了李和仪的定理1.1和1.2(Bull Korean Math Soc 53(4):1213-1235,2016)。