The first time I saw this, I was hooked! You can’t “unsee” it and you don’t want to forget it because the fact that it is true is so amazing. This is just the start of a more general theory in mathematics that I will briefly touch upon at the end of the article.
Not only is this amazing, but it is also one of the most useful tools in number theory. Let’s try to understand this together by going through a simple example.