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arXiv · 1212.0836

An Improved Lower Bound for Stack Sorting

Luke Schaeffer
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Abstract

We consider the problem of sorting elements on a series of stacks, introduced by Tarjan and Knuth. We improve the asymptotic lower bound for the number of stacks necessary to sort $n$ elements to $0.561 \log_2 n + O(1)$. This is the first significant improvement since the previous lower bound, $1/2 \log_2 n + O(1)$, was established by Knuth in 1972.

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Luke Schaeffer. 2012-12-04. An Improved Lower Bound for Stack Sorting. https://arxiv.org/abs/1212.0836

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