Word Problem Languages for Free Inverse Monoids

  • Tara BroughEmail author
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 10952)


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.


Word problems Co-word problems Inverse monoids ET0L languages Stack automata Poly-context-free languages 


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Authors and Affiliations

  1. 1.Centro de Matemática e Aplicações, Faculdade de Ciências e TecnologiaUniversidade Nova de LisboaCaparicaPortugal

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