At: one2one preserves fin 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
1. T: Type
2. U: Type
3. f: T
U
4. g: U
T
5. g o f = Id
6. f o g = Id
7. n: 
8. f1:
n
T
9.
a1,a2:
n. f1(a1) = f1(a2) 
a1 = a2
10. Surj(
n; T; f1)
11. a1:
n
12. a2:
n
13. (f o f1)(a1) = (f o f1)(a2)
14. f1(a1) = f1(a2)
a1 = a2
By: InstHyp [a1;a2] 9
Generated subgoals:None
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