At:
paren order1
3
2
2
1
1.
T: Type
2.
s: (T+T) List
3.
t: T
4.
i:T, s1,s2:(T+T) List. s = (s1 @ [inl(i)] @ s2) 
(inr(i) 
s2)
5.
paren(T;s)
6.
i: T
7.
s1: (T+T) List
8.
s2: (T+T) List
9.
([inl(t)] @ s @ [inr(t)]) = (s1 @ [inl(i)] @ s2)
10.
e: (T+T) List
11.
s1 = ([inl(t)] @ e)
12.
(s @ [inr(t)]) = (e @ [inl(i)] @ s2)
13.
e1: (T+T) List
14.
e = (s @ e1)
15.
[inr(t)] = (e1 @ [inl(i)] @ s2)
16.
e1 = nil
17.
([inl(i)] @ s2) = [inr(t)]
(inr(i) s2)
By:
ObviousContradiction [-1]
Generated subgoals:
None
About:
