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DeBruijnMorselt ​

The right-branch bijection to binary trees followed by the left-branch bijection back: the de Bruijn-Morselt automorphism of the ordered trees.

DeBruijnMorselt(OrderedTree)The right-branch bijection to binary trees followed by the left-branch bijection back: the de Bruijn-Morselt automorphism of the ordered trees.
Typed signatures
TypePackageApplies
(ordered_tree) -> ordered_treecombinatoricsalways

Domain: Combinatorial maps

Details
  • Takes a OrderedTree and returns a OrderedTree — a typed map, so a wrong carrier is a type error rather than a wrong answer.
  • Defined as a COMPOSITION, applied right to left: OrderedTree after RightBranchBinaryTree. Each step goes through its own declared head, so every intermediate value is a properly constructed carrier.
  • FindStat's Mp00328. Chaotic in general: Shapiro shows its sixth power is the identity on the trees that correspond to compositions.

Examples

Basic #

an ordered tree with four edges

live ↗
InDeBruijnMorselt(OrderedTree⁡([[[],[]],[]]))\mathrm{DeBruijnMorselt}({\operatorname{OrderedTree}}(\bigl\lbrack\bigl\lbrack\bigl\lbrack\bigr\rbrack, \bigl\lbrack\bigr\rbrack\bigr\rbrack, \bigl\lbrack\bigr\rbrack\bigr\rbrack))OutOrderedTree⁡([[[]],[[]]]){\operatorname{OrderedTree}}(\bigl\lbrack\bigl\lbrack\bigl\lbrack\bigr\rbrack\bigr\rbrack, \bigl\lbrack\bigl\lbrack\bigr\rbrack\bigr\rbrack\bigr\rbrack)
About
Examples1
CrosswalkFindStat

See also: OrderedTree, RightBranchBinaryTree