Acta Informatica

, Volume 28, Issue 7, pp 703–712 | Cite as

Postorder trees and Eulerian numbers

  • Thomas P. Whaley


Binary search trees built from the postorder traversal sequence of other binary search trees are characterized in terms of their binary tree structure. A connection is established between this structure and the Eulerian numbers. This yields considerable information concerning the “average” binary search tree with a given number of nodes. Periodicity is established for the process of repeatedly taking postorder sequences and building binary search trees. Finally, the average depth of a node in a postorder tree withn nodes is determined.


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Copyright information

© Springer-Verlag 1991

Authors and Affiliations

  • Thomas P. Whaley
    • 1
  1. 1.Department of Computer ScienceWashington and Lee UniversityLexingtonUSA

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