(22steps total) PrintForm Definitions Lemmas mb event system 1 Sections EventSystems Doc
IF YOU CAN SEE THIS go to /sfa/Nuprl/Shared/Xindentation_hack_doc.html
At: select concat 2

1. T : Type
2. (T List) List
3. u : T List
4. v : (T List) List
5. n:||concat(v)||. 
5. m:||v||. 
5. ||concat(firstn(m;v))||n
5. n-||concat(firstn(m;v))||<||v[m]||
5. & concat(v)[n] = v[m][(n-||concat(firstn(m;v))||)]
  n:||concat([u / v])||. 
  m:||[u / v]||. 
  ||concat(firstn(m;[u / v]))||n
  n-||concat(firstn(m;[u / v]))||<||[u / v][m]||
  & concat([u / v])[n] = [u / v][m][(n-||concat(firstn(m;[u / v]))||)]


By: Unfold `concat` 0 THEN Reduce 0 THEN Try (Fold `concat` 0)


Generated subgoal:

1   n:||u @ concat(v)||. 
  m:(||v||+1). 
  ||concat(firstn(m;[u / v]))||n
  n-||concat(firstn(m;[u / v]))||<||[u / v][m]||
  & (u @ concat(v))[n] = [u / v][m][(n-||concat(firstn(m;[u / v]))||)]

19 steps

About:
listconsnatural_numberaddsubtractless_thanuniverseequalallexists
IF YOU CAN SEE THIS go to /sfa/Nuprl/Shared/Xindentation_hack_doc.html

(22steps total) PrintForm Definitions Lemmas mb event system 1 Sections EventSystems Doc