nil ; h.l' [h; f(h)/ (+f)(l')] (recursive)
Thm* 
St:Type, l:St*, f:(St
St). (+f)(l) 
St*
False ; b.bs' b = a T 
mem_f(T;a;bs')
(recursive)
Thm* T:Type, a:T, bs:T*. mem_f(T;a;bs) Prop
| add_action |
Def (+f)(l) == Case of l; nil nil ; h.l' [h; f(h)/ (+f)(l')] (recursive)
Thm* |
| mem_f |
Def mem_f(T;a;bs) == Case of bs; nil False ; b.bs' b = a T mem_f(T;a;bs')
(recursive)
Thm* |
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