reserve phi,fi,psi for Ordinal-Sequence,
  A,A1,B,C,D for Ordinal,
  f,g for Function,
  X for set,
  x,y,z for object;
reserve f1,f2 for Ordinal-Sequence;
reserve W for Universe;
reserve A1,B1 for Ordinal of W,
  phi for Ordinal-Sequence of W;
reserve L for Sequence;
reserve e,u for set;

theorem 
  for A, B being Sequence holds rng B c= rng(A^B) by Th8A;
