Cardinality of the Dickson permutation's group of polynomials on ${\mathbb{Z}}_n$

Abstract

Let $G_n$ be the group of permutations on ${\mathbb{Z}}_n$ that is induced by a Dickson polynomial, where $n$ is a positive integer. In this work, by solving special types of systems of linear congruences, we obtain $G_n$. In addition, we give an a algorithm that gets $|G_n|$.