Skip to content

NoncrossingPermutation ​

The noncrossing permutation Stump's bijection gives the path: the cycles of its touch points, peeled off round by round.

NoncrossingPermutation(DyckPath)The noncrossing permutation Stump's bijection gives the path: the cycles of its touch points, peeled off round by round.
Typed signatures
TypePackageApplies
(dyck_path) -> permutationcombinatoricsalways

Domain: Combinatorial maps

Details
  • Takes a DyckPath and returns a Permutation — a typed map, so a wrong carrier is a type error rather than a wrong answer.
  • FindStat's Mp00023, Sage's to_noncrossing_permutation. Injective: its image is the noncrossing permutations. It sends the area to the number of inversions.

Examples

Basic #

the Dyck path UUDDUDUUDDUD

live ↗
InNoncrossingPermutation(DyckPath⁡([1,1,0,0,1,0]))\mathrm{NoncrossingPermutation}({\operatorname{DyckPath}}([1, 1, 0, 0, 1, 0]))OutPermutation⁡([2,1,3]){\operatorname{Permutation}}([2, 1, 3])
About
Examples1
CrosswalkFindStat