Zell: It's the powers of 5. It starts with a single brush, which then gains four brushes at the sides: 1+4 = 5 = 5^1. The next one is the 5^1 set, with four other 5^1 sets configured the same way: 5^1 * 5 = 5^2 = 25, and so on. There are 7 sets, with the largest being 5^6 = 15625.
You can continue this process indefinitely, with any equilateral pyramid. I got the idea from an Ubuntu screensaver that did it with triangular pyramids.
Daft_Vader: You aren't. It's just for looks. Though if you wanted me to make a big, big map of it...
Freyr's now telling me to try the Mandlebrot set.
