data.nat
========

The natural numbers.

* [basic](basic.lean) : the natural numbers, with succ, pred, addition, and multiplication
* [order](order.lean) : less-than, less-then-or-equal, etc.
* [bquant](bquant.lean) : bounded quantifiers
* [sub](sub.lean) : subtraction, and distance
* [div](div.lean) : div, mod, gcd, and lcm