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arXiv · 2511.00566

Free inverse monoids are co-context-free

Tara Macalister Brough·Marianne Johnson·Mark Kambites·Carl-Fredrik Nyberg-Brodda
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Abstract

We prove (using grammars) that the free inverse monoid of every finite rank has co-context-free word problem. Equivalently, the co-word problem of the free inverse monoid of every finite rank is context-free.

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Tara Macalister Brough, Marianne Johnson, Mark Kambites, Carl-Fredrik Nyberg-Brodda. 2025-11-01. Free inverse monoids are co-context-free. https://arxiv.org/abs/2511.00566

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