Divisibility Relations Between Ring Homomorphisms and Surjective Group Homomorphisms in Finite Cyclic Structures

Abstract: In this article, we delve into the intricate relationship between the number of ring homomorphisms and surjective group homomorphisms between two finite cyclic structures, specifically $\mathbb{Z}_m$ and $\mathbb{Z}_n$. We demonstrate that the number of ring homomorphisms from $\mathbb{Z}_m$ to $\mathbb{Z}_n$ is a divisor of the number of surjective group homomorphisms from $\mathbb{Z}_m$ to $\mathbb{Z}_n$, provided that $n$ is not of the form $2 \cdot \alpha$, where each prime factor $p$ of $\alpha$ satisfies $p \equiv 3 \pmod{4}$.