The r-Major Index
Copyright © 1981 Elsevier.
The r-major index is a new permutation statistic that is suggested by the work of Carlitz and Gausner on Foulkes' skew hook rule for computing the r-Eulerian numbers. The new statistic (1) generalizes both the major index and the inversion number of a permutation and (2) leads to a q-analog of the r-Eulerian numbers.
Don Rawlings. "The r-Major Index" Journal of Combinatorial Theory, Series A 31 (1981): 175-183.
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