begin
theorem Th1:
theorem Th2:
theorem Th3:
theorem Th4:
theorem Th5:
theorem Th6:
begin
:: deftheorem Def1 defines value NUMERAL1:def 1 :
:: deftheorem Def2 defines digits NUMERAL1:def 2 :
theorem Th7:
theorem Th8:
begin
theorem Th9:
theorem
theorem
theorem
theorem