| Some definitions of interest. |
|
absval | Def |i| == if 0 i i else -i fi |
| | Thm* x: . |x|  |
|
gcd | Def gcd(a;b) == if b= 0 a else gcd(b;a rem b) fi (recursive) |
| | Thm* a,b: . gcd(a;b)  |
|
gcd_p | Def GCD(a;b;y) == y | a & y | b & ( z: . z | a & z | b  z | y) |
| | Thm* a,b,y: . GCD(a;b;y) Prop |
|
nat | Def == {i: | 0 i } |
| | Thm* Type |