At: append segment 1 1 1 1 1 1 2 1 1 1 1 1 1 1 1 1 1 1 1 1 2 2 1
1. T: Type
2. as: T*
3. i: {0...||as||}
4. j: {i...||as||}
5. k: {j...||as||}
6. x: 
7. 0 < x
8. k
x+i
9. tl(nth_tl(-1+i+x;as)) = nth_tl(i+x;as)
10. aas: T*
11. u: T
12. v: T*
hd((u.v)).firstn(-i+k+-x;tl((u.v))) = firstn(1+-i+k+-x;u.v)
By:
RWH (AddrC [3] (RecUnfoldC `firstn`)) 0
THEN
Reduce 0
THEN
SplitOnConclITE
Generated subgoals:None
About:
