theorem
  for f being n-element real-valued FinSequence holds f in REAL n
  proof
    let f be n-element real-valued FinSequence;
    rng f c= REAL;
    then f is FinSequence of REAL by FINSEQ_1:def 4;
    then
A1: f is Element of REAL* by FINSEQ_1:def 11;
    len f = n by CARD_1:def 7;
    hence thesis by A1;
  end;
