reserve a,b,c,d for Ordinal;
reserve l for non empty limit_ordinal Ordinal;
reserve u for Element of l;
reserve A for non empty Ordinal;
reserve e for Element of A;
reserve X,Y,x,y,z for set;
reserve n,m for Nat;
reserve f for Ordinal-Sequence;
reserve U,W for Universe;
reserve F,phi for normal Ordinal-Sequence of W;
reserve g for Ordinal-Sequence-valued Sequence;
reserve U for uncountable Universe;

theorem Th74:
  U-Veblen.1 = criticals(U exp omega)
  proof set o = succ(0-element_of U);
    o in On U by ORDINAL1:def 9; then
    U-Veblen.1 = criticals(U-Veblen.0) by Def15;
    hence thesis by Def15;
  end;
