IF YOU CAN SEE THIS go to /sfa/Nuprl/Shared/Xindentation_hack_doc.html
At:
compose iter sum12 1. A : Type
2. x : A 3. f : AA 4. i : 5. i1:. i1<i (j,k:. k = i1+jf{i1}(f{j}(x)) = f{k}(x))
6. j : 7. k : 8. k = i+j 9. i = 0
f{i}(f{j}(x)) = f{k}(x)
By:
Rewrite by Thm*f:(AA), i:, x:A. f{i}(x) = f(f{i-1}(x))