
theorem
  for f be FinSequence of INT holds ex f1,f2 be FinSequence of NAT st
    f = f1 - f2
  proof
    let f be FinSequence of INT;
    reconsider f1 = delneg f as FinSequence of NAT by NEWTON02:103;
    reconsider f2 = delpos f as FinSequence of NAT by NEWTON02:103;
    f = f1 - f2 by DNP;
    hence thesis;
  end;
