FoataMajorToInversions from BinaryWord
Foata's bijection on words: each letter is put on the end of the image so far, which is cut into blocks, and every block is rotated one place right.
FindStat's Mp00096. With repeated letters an equal letter counts as the smaller, so it is the permutation map through standardization; it sends the major index to the number of inversions.
Called as CombinatorialMap(x, "FoataMajorToInversions"). The head's page has its examples.
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Explore
Each element of BinaryWord at a size, and its image, applied in your browser; sizes past 6 are not offered.
Properties
Transport a statistic
Pick a statistic on BinaryWord. Its distribution over the images of BinaryWord at each size is computed, and compared with the 59 statistics on BinaryWord: those that share it are the ones the map sends it to, as far as the sizes computed show.
Also from
The same name out of other carriers, each its own implementation: Permutation, IntegerComposition.
FindStat Mp00096
Foata bijection
Matched by value: our map agrees with FindStat's image on each of the 126 rows of size at most 6 we can read (0 unread; its table has 1200 rows).
BijectionGraded mapas FindStat records them, checked by FindStat's contributors.
| Object | Image |
|---|---|
0 | 0 |
1 | 1 |
00 | 00 |
01 | 01 |
Data from FindStat, the combinatorial statistic finder; the page at findstat.org/Mp00096 has the rest.