TailPairsOfOccurrencesOf321 on Permutation
Pairs j < k with p(j) > p(k) and some entry before j above p(j), the positions of the 2 and the 1 of the occurrences of 321.
Called as CombinatorialStat(x, "TailPairsOfOccurrencesOf321"). The head's page has its examples.
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FindStat St000123
The difference in Coxeter length of a permutation and its image under the Simion-Schmidt map.
| Object | Value |
|---|---|
[] | 0 |
[1] | 0 |
[1,2] | 0 |
[2,1] | 0 |
[1,2,3] | 0 |
[1,3,2] | 0 |
[2,1,3] | 0 |
[2,3,1] | 0 |
Data from FindStat, the combinatorial statistic finder; the page at findstat.org/St000123 has the rest.