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arXiv · 1711.06040

Permutations sorted by a finite and an infinite stack in series

Murray Elder·Yoong Kuan Goh
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Abstract

We prove that the set of permutations sorted by a stack of depth $t \geq 3$ and an infinite stack in series has infinite basis, by constructing an infinite antichain. This answers an open question on identifying the point at which, in a sorting process with two stacks in series, the basis changes from finite to infinite.

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Murray Elder, Yoong Kuan Goh. 2018-01-02. Permutations sorted by a finite and an infinite stack in series. https://arxiv.org/abs/1711.06040

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