reserve n for non zero Nat,
  j,k,l,m for Nat,
  g,h,i for Integer;

theorem
  for l,m be Nat st l,m are_congruent_mod 2 to_power n holds n
  -BinarySequence(l) = n-BinarySequence(m)
proof
  let l,m be Nat;
  assume l,m are_congruent_mod 2 to_power n;
  then (l qua Integer) mod 2 to_power n = (m qua Integer) mod 2 to_power n by
NAT_D:64;
  hence thesis by Th30;
end;
