% ...
  PermsSorted = Perms.sort(),
  P1Sorted = P1.sort(),
  Found2 = false,
  foreach({P,PP} in zip(PermsSorted,P1Sorted ++ ["DUMMY"]), Found2 = false)
    if P != PP then
      println(missing8=P),
      Found2 := true
    end
  end,

  A = [cond(P == PP,1,0) : {P,PP} in zip(PermsSorted,P1Sorted ++ ["DUMMY"])],
  println(missing9=[PermsSorted[I] : I in 1..PermsSorted.length, A[I] = 0].first()),

  % shorter
  println(missing10=[P:{P,PP} in zip(PermsSorted,P1Sorted ++ ["DUMMY"]), P != PP].first()),