reserve n,m for Nat;

theorem Th29:
  for f being real-valued FinSequence holds
  dom (sort_a f)=dom f & len (sort_a f)=len f
proof
  let f be real-valued FinSequence;
  f,(sort_a f) are_fiberwise_equipotent by Def6;
  hence thesis by RFINSEQ:3;
end;
