
theorem
  ex F being sequence of [:NAT,NAT:]
  st F is one-to-one & dom F = NAT & rng F = [:NAT,NAT:]
proof
  consider F being Function such that
A1: F is one-to-one and
A2: dom F = NAT & rng F = [:NAT,NAT:] by CARD_4:5,WELLORD2:def 4;
  F is sequence of [:NAT,NAT:] by A2,FUNCT_2:1;
  hence thesis by A1,A2;
end;
