You do a lot of messy work, and then you clean it up when you are done. https://gowers.wordpress.com/2011/11/18/proving-the-fundamental-theorem-of-arithmetic/

You do a lot of messy work, and then you clean it up when you are done. https://gowers.wordpress.com/2011/11/18/proving-the-fundamental-theorem-of-arithmetic/ https://gowers.wordpress.com/2011/11/18/proving-the-fundamen...