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arXiv · 1511.00473

$2\times 2$ monotone grid classes are finitely based

Michael Albert·Robert Brignall
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Abstract

In this note, we prove that all $2 \times 2$ monotone grid classes are finitely based, i.e., defined by a finite collection of minimal forbidden permutations. This follows from a slightly more general result about certain $2 \times 2$ (generalized) grid classes having two monotone cells in the same row.

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Michael Albert, Robert Brignall. 2016-02-08. $2\times 2$ monotone grid classes are finitely based. https://doi.org/10.46298/dmtcs.1325

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