CallanSwitch from SetPartition
Callan's involution: switches the first closer with the lesser of the least closer and the second element of the block of 1.
FindStat's Mp00249, a joint symmetry of St000971 and St001784.
Called as CombinatorialMap(x, "CallanSwitch"). The head's page has its examples.
Live
Explore
Each element of SetPartition 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 SetPartition at each size is computed, and compared with the 111 statistics on SetPartition: those that share it are the ones the map sends it to, as far as the sizes computed show.
FindStat Mp00249
Callan switch
Matched by value: our map agrees with FindStat's image on each of the 278 rows of size at most 6 we can read (0 unread; its table has 1200 rows).
BijectionGraded mapInvolutionas FindStat records them, checked by FindStat's contributors.
| Object | Image |
|---|---|
{{1}} | {{1}} |
{{1,2}} | {{1,2}} |
{{1,2,3}} | {{1,3},{2}} |
{{1},{2}} | {{1},{2}} |
Data from FindStat, the combinatorial statistic finder; the page at findstat.org/Mp00249 has the rest.