theorem Th11:
  for p being FinSequence of D holds <*p*> is Matrix of 1,len p,D
proof
  let p be FinSequence of D;
  reconsider p9 = p as Element of (D)* by FINSEQ_1:def 11;
  <*p9*> is tabular by Th3;
  then reconsider M = <*p*> as Matrix of D;
  M is (1,len p)-size
  proof
    thus len M = 1 by FINSEQ_1:39;
    let q;
    assume q in rng M;
    then q in { p } by FINSEQ_1:38;
    hence thesis by TARSKI:def 1;
  end;
  hence thesis;
end;
