“…A great amount of research in combinatorics and computer science has focused on sorting operators, which are dynamical systems on S n that have the identity permutation e = 123 • • • n as their unique periodic (necessarily fixed) point. Some typical examples of such operators include the bubble sort map (see [17,2] and [37, pages 106-110]), West's stack-sorting map (see [10,21,22,26,53] and the references therein), the map revstack defined in [28], the pop-stack-sorting map [4,5,6,29,19,20,45,52], and the Queuesort map [18,40].…”