Thm* n:, x:(nn). (x n) < n div_bounds_2
Thm* n,m:. f:(nm(nm)). Bij(nm; (nm); f) rect_enumer
In prior sections: int 1 int 2
n:
, x:(n
n). (x 
n) < n div_bounds_2
== {i:
| 0 < i }
n:, x:(nn). (x n) < n div_bounds_2
n,m:. 
f:(n
m
(nm)). Bij(nm; (nm); f) rect_enumer