Year: 2026
Type: preprint
Abstract: Let $δ\in\mathbb{F}_{2^n}$ satisfy $\operatorname{Tr}_{\mathbb{F}_{2^n}/\mathbb{F}_2}(δ)=1$. We study the permutation behavior of $$ f(x) = \left(\frac{1}{x^2+x+δ}\right)^{2^k}+x $$ over $\mathbb{F}_{2^n}$. Helleseth and Zinoviev proved that $f(x)$ is a permutation for $k=0,1$, and remarked that numerical evidence suggests that no other cases occur. In this paper, we confirm their assertion by proving that, for $0\leq k
Source: arXiv (Cornell University)
Author: Li, Yi
Institution: Shanghai Jiao Tong University
Language: English
Subfield: Discrete Mathematics and Combinatorics
Field: Mathematics
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W7208758897