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arXiv · 1803.08034

Word Problem Languages for Free Inverse Monoids

Tara Brough
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Abstract

This paper considers the word problem for free inverse monoids of finite rank from a language theory perspective. It is shown that no free inverse monoid has context-free word problem; that the word problem of the free inverse monoid of rank $1$ is both $2$-context-free (an intersection of two context-free languages) and ET0L; that the co-word problem of the free inverse monoid of rank $1$ is context-free; and that the word problem of a free inverse monoid of rank greater than $1$ is not poly-context-free.

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Tara Brough. 2018-03-21. Word Problem Languages for Free Inverse Monoids. https://arxiv.org/abs/1803.08034

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