reserve i, j, k, c, m, n for Nat,
  a, x, y, z, X, Y for set,
  D, E for non empty set,
  R for Relation,
  f, g for Function,
  p, q for FinSequence;

theorem Th28:
  for f being len-total to-naturals homogeneous NAT*-defined Function holds
  f is quasi_total Element of HFuncs NAT
proof
  let f be len-total to-naturals homogeneous NAT*-defined Function;
  reconsider f9=f as Element of HFuncs NAT by Th27;
  f9 is quasi_total
  by Def2;
  hence thesis;
end;
