At:
list exists is member lemma221111
1.
T: Type
2.
eq: TT
3.
x,y:T. eq(x,y) x = y
4.
eq TT
5.
P: TProp
6.
L: T List
7.
u: T
8.
v: T List
9.
yv.P(y) (x:T. x(eq) v & P(x))
10.
P(u)
if eq(u,u) true else u(eq) v fi
By:
Witness3 u
THEN
With u (Analyze -1)
Generated subgoal: