FixedPointMajorIndex on Permutation
The sum of the fixed points less the triangular number of their count, plus the major index of the word without its fixed points.
Called maf.
Called as CombinatorialStat(x, "FixedPointMajorIndex"). The head's page has its examples.
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FindStat St000339
The maf index of a permutation.
| Object | Value |
|---|---|
[1] | 0 |
[1,2] | 0 |
[2,1] | 1 |
[1,2,3] | 0 |
[1,3,2] | 1 |
[2,1,3] | 3 |
[2,3,1] | 2 |
[3,1,2] | 1 |
Data from FindStat, the combinatorial statistic finder; the page at findstat.org/St000339 has the rest.