MacMahonEqualIndex on DyckPath
The sum of the positions of double rises and double falls: MacMahon's equal index of the step word.
Called as CombinatorialStat(x, "MacMahonEqualIndex"). The head's page has its examples.
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Distribution
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FindStat St000977
MacMahon's equal index of a Dyck path.
| Object | Value |
|---|---|
[1,0,1,0] | 0 |
[1,1,0,0] | 4 |
[1,0,1,0,1,0] | 0 |
[1,0,1,1,0,0] | 8 |
[1,1,0,0,1,0] | 4 |
[1,1,0,1,0,0] | 6 |
[1,1,1,0,0,0] | 12 |
[1,0,1,0,1,0,1,0] | 0 |
Data from FindStat, the combinatorial statistic finder; the page at findstat.org/St000977 has the rest.