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arXiv · 1604.01723

Postorder Preimages

Colin Defant
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Abstract

Given a set $Y$ of decreasing plane trees and a permutation $π$, how many trees in $Y$ have $π$ as their postorder? Using combinatorial and geometric constructions, we provide a method for answering this question for certain sets $Y$ and all permutations $π$. We then provide applications of our results to the study of the deterministic stack-sorting algorithm.

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Colin Defant. 2018-06-02. Postorder Preimages. https://doi.org/10.23638/dmtcs-19-1-3

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