0 ; a.as' ||as'||+1 (recursive)
Thm* 
A:Type, l:A*. ||l|| 
Thm* ||nil||
A == A 
False
Thm* A:Prop. (A) Prop
| length |
Def ||as|| == Case of as; nil 0 ; a.as' ||as'||+1 (recursive)
Thm*
Thm* ||nil|| |
| not |
Def A == A False
Thm* |
About:
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