On The Type Of Permutations
Wang Jie · Acta Scicentiarum Naturalum Universitis Pekinesis · 1990
In this paper we determine the necessary and sufficient condition for any triple of non-negative integers (s, i, d) to be the type of some n-permutation. An equival- ence relation is defined on the set of all n-permutations according to their types. The formulas for calculating the numbers of equivalence classes and the permutations contained in each class are presented.