2 papers
math.GR2025
Free inverse monoids are co-context-free
Tara Macalister Brough, Marianne Johnson, Mark Kambites +1
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…
math.GR2025
Preserving self-similarity in free products of semigroups
Tara Macalister Brough, Jan Philipp Wächter, Janette Welker
We improve on earlier results on the closure under free products of the class of automaton semigroups. We consider partial automata and show that the free product of two self-simil…