ar X iv : 1 30 2 . 24 55 v 1 [ m at h . G R ] 1 1 Fe b 20 13 Rational subsets and submonoids of wreath products ⋆
نویسندگان
چکیده
It is shown that membership in rational subsets of wreath products H ≀ 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 ≀ Z with an undecidable membership problem.
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