There are all kinds of interesting facts ahout prime numbers. This chapter collates some of the ones I personally find amazing. What are your favorites?

Along those lines, I have to mention one of the best web sites about primes. This is the Prime Pages, hosted at the University of Tennessee, Martin. It's just amazingly full of useful information, but also quite user-friendly and usable for a large variety of backgrounds. In particular, the top twenty page has links to the top twenty of just about every prime type you can imagine, a cornucopia of information. I really like, for instance, the prediction of when the first billion digit prime will surface.

Another interesting resource is Numberphile's YouTube channel for prime videos.

At the same time as we finish up our exploration of the wacky and wonderful world of primes, and start heading back toward other arithmetic functions, we keep an eye toward developing the language we'll need to explore \(\pi(x)\) more rigorously.