IF YOU CAN SEE THIS go to /sfa/Nuprl/Shared/Xindentation_hack_doc.html
At:
select nth tl T:Type, as:T List, n:{0...||as||}, i:(||as||-n).
nth_tl(n;as)[i] = as[(i+n)]
By:
(CDToVarThen `as' ListInd) THEN (Reduce 0)
Generated subgoals:
1
1. T : Type
2. T List
n:{0...0}, i:(0-n). nth_tl(n;nil)[i] = nil[(i+n)] T
1. T : Type
2. T List
3. u : T 4. v : T List
5. n:{0...||v||}, i:(||v||-n). nth_tl(n;v)[i] = v[(i+n)]
n:{0...||v||+1}, i:(||v||+1-n). nth_tl(n;u.v)[i] = (u.v)[(i+n)]
5 steps
About:
IF YOU CAN SEE THIS go to /sfa/Nuprl/Shared/Xindentation_hack_doc.html