Published online by Cambridge University Press: 06 November 2023
We prove a difference analogue of the celebrated Tumura–Hayman–Clunie theorem. Let f be a transcendental entire function, let c be a nonzero constant and let n be a positive integer. If f and $\Delta _c^n f$ omit zero in the whole complex plane, then either
$f(z)=\exp (h_1(z)+C_1 z)$, where
$h_1$ is an entire function of period c and
$\exp (C_1 c)\neq 1$, or
$f(z)=\exp (h_2(z)+C_2 z)$, where
$h_2$ is an entire function of period
$2c$ and
$C_2$ satisfies
$$ \begin{align*} \bigg(\frac{1+\exp(C_2c)}{1-\exp(C_2 c)}\bigg)^{2n}=1. \end{align*} $$
This work was partially supported by the National Natural Science Foundation of China (Grant Nos. 12171127, 12071047, 12301096, 11901311, 12371074) and National Key Technologies R&D Program of China (2020YFA0713300).