Learning the Games
How a roulette wheel is laid out, and why the order looks random
The numbers around a wheel head are not in counting order, and they are not scattered at random either. The ring is arranged so that colours, high numbers and odd numbers are spread as evenly as the geometry allows.
Look down at a single-zero wheel and the first thing that fails to appear is any sequence you would recognise. One is not beside two. Thirty-six is not beside thirty-five. The green zero sits at the top of the ring and the numbers run away from it in an order that seems to have been shaken out of a bag.
It was not shaken out of anything. The ring on a single-zero wheel holds thirty-seven pockets: the numbers one to thirty-six, and a single green zero. The order is fixed, it is the same on every wheel of that type, and it is built to satisfy several constraints at once.