IF YOU CAN SEE THIS go to /sfa/Nuprl/Shared/Xindentation_hack_doc.html
At:
flip adjacent112 1. k : 2. k 3. k 4. n : 5. 0<n 6. x,y:k. y-x = n-1 (L:(k-1) List. (x, y) = compose_flips(L))
7. x1 : k 8. y1 : k 9. y1-x1 = n L:(k-1) List. (x1, y1) = compose_flips(L)