Rational Subsets and Submonoids of Wreath Products
Markus Lohrey, Benjamin Steinberg, Georg Zetzsche · arXiv (Cornell University) · 2013
It is shown that membership in rational subsets of wreath products H \wr V with H a finite group and V a virtually free group is decidable. On the other hand, it is shown that there exists a fixed finitely generated submonoid in the wreath product Z \wr Z with an undecidable membership problem.