0 ; a.as' ||as'||+1 (recursive)
A:Type, l:A List. ||l|| 
T:Type, L:T List. ||L|| 
== {i:| 0
i } TypeB == 
B < Ai,j:. (ij) PropA == A 
FalseA:Prop. (A) Prop| Who Cites length? | |
| length | Def ||as|| == Case of as; nil 0 ; a.as' ||as'||+1 (recursive) |
| Thm* A:Type, l:A List. ||l|| | |
| Thm* ||nil|| | |
| Thm* T:Type, L:T List. ||L|| | |
| nat | Def == {i:| 0i } |
| Thm* Type | |
| le | Def AB == B < A |
| Thm* i,j:. (ij) Prop | |
| not | Def A == A False |
| Thm* A:Prop. (A) Prop |
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