NoncrossingPartition from DyckPath
Biane's noncrossing set partition: the up steps whose matching downs lie in one run of downs form a block.
FindStat's Mp00138. Injective: it reaches exactly the noncrossing partitions.
Called as CombinatorialMap(x, "NoncrossingPartition"). The head's page has its examples.
Live
Explore
Each element of DyckPath at a size, and its image, applied in your browser; sizes past 7 are not offered.
Properties
Transport a statistic
Pick a statistic on SetPartition. Its distribution over the images of DyckPath at each size is computed, and compared with the 171 statistics on DyckPath: those that share it are the ones the map sends it to, as far as the sizes computed show.
FindStat Mp00138
to noncrossing partition
Matched by value: our map agrees with FindStat's image on each of the 196 rows of size at most 6 we can read (0 unread; its table has 1200 rows).
InjectionGraded mapas FindStat records them, checked by FindStat's contributors.
| Object | Image |
|---|---|
[1,0] | {{1}} |
[1,0,1,0] | {{1},{2}} |
[1,1,0,0] | {{1,2}} |
[1,0,1,0,1,0] | {{1},{2},{3}} |
Data from FindStat, the combinatorial statistic finder; the page at findstat.org/Mp00138 has the rest.