Fermat's Little Theorem

August 2, 2024

This is an oldie, but a cute little trick to solving Fermat’s Little Theorem that I came across back when I was an undergraduate. This is a well known proof and can be found in Wikipedia1, although I found this proof in an article posted by Fermat’s Library 2. Theorem  (Fermat's Little Theorem) If $p$ is a prime number and $p \nmid n$ for $n \in \mathbb{N}$, then $n^p \equiv n \mod p$. ...