Let $G$ be the group of units of the commutative group $\mathbb{Z}/2007\mathbb{Z}$ and consider the group homomorphism $h\colon G\to G$ where $h(g)=g^n$ for $n\ge1$.
How can I find the order of $\ker h$?
Let $G$ be the group of units of the commutative group $\mathbb{Z}/2007\mathbb{Z}$ and consider the group homomorphism $h\colon G\to G$ where $h(g)=g^n$ for $n\ge1$.
How can I find the order of $\ker h$?