Affiliation:
1. Dipartimento di Matematica e Informatica “U. Dini” , Università degli Studi di Firenze , Firenze , Italy
Abstract
Abstract
Following the footprints of what has been done with other sorting devices, we study a popqueue and define an optimal sorting algorithm, called Cons. Our results include a description of the set of all the preimages of a given permutation, an enumeration of the set of the preimages of permutations with some specific properties and, finally, the exact enumeration of permutations having 0, 1 and 2 preimages, respectively, with a characterization of permutations having 3 preimages.
Reference9 articles.
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