theorem Th16:
  n>0 implies min* f"{m} <= n-1
proof
A1: f"{m} c= n
  proof
    let x be object;
    assume x in f"{m};
    then x in dom f by FUNCT_1:def 7;
    hence thesis;
  end;
  assume n>0;
  hence thesis by A1,Th14;
end;
