reserve x for set,
  t,t1,t2 for DecoratedTree;
reserve C for set;
reserve X,Y for non empty constituted-DTrees set;
reserve T for DecoratedTree,
  p for FinSequence of NAT;
reserve T for finite-branching DecoratedTree,
  t for Element of dom T,
  x for FinSequence,
  n, m for Nat;

theorem Th36:
  succ(T,t) = T*(t succ)
proof
  ex q being Element of dom T st q = t & succ(T,t) = T*(q succ) by Def6;
  hence thesis;
end;
