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Simple permutations: decidability and unavoidable substructures

Robert Brignall·Nik Ruskuc·Vince Vatter
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Abstract

We prove that it is decidable if a finitely based permutation class contains infinitely many simple permutations, and establish an unavoidable substructure result for simple permutations: every sufficiently long simple permutation contains an alternation or oscillation of length k.

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Robert Brignall, Nik Ruskuc, Vince Vatter. 2006-09-07. Simple permutations: decidability and unavoidable substructures. https://arxiv.org/abs/math/0609211

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