At:
non nil is member12
1.
T: Type
2.
eq: {T}
3.
eq TT
4.
x:T. eq(x,x)
5.
x,y:T. eq(x,y) eq(y,x)
6.
x,y,z:T. eq(x,y) eq(y,z) eq(x,z)
7.
L: T List
8.
u: T
9.
v: T List
10.
v nil (x:T. x(eq) v)
u.v nil (x:T. x(eq) (u.v))
By:
Analyze 0
THEN
Witness u
Generated subgoal: