reserve a, b, k, n, m for Nat,
  i for Integer,
  r for Real,
  p for Rational,
  c for Complex,
  x for object,
  f for Function;

theorem Th12:
  divSeq(m,n).1 = n div modSeq(m,n).0
proof
  thus divSeq(m,n).1 = n div (m mod n) by Def2
    .= n div modSeq(m,n).0 by Def1;
end;
