Pointlike sets for varieties determined by groups

نویسندگان

  • Samuel Jacob van Gool
  • Benjamin Steinberg
چکیده

For a variety of finite groups $\mathbf H$, let $\overline{\mathbf H}$ denote the variety of finite semigroups all of whose subgroups lie in $\mathbf H$. We give a characterization of the subsets of a finite semigroup that are pointlike with respect to $\overline{\mathbf H}$. Our characterization is effective whenever $\mathbf H$ has a decidable membership problem. In particular, the separation problem for $\overline{\mathbf H}$-languages is decidable for any decidable variety of finite groups $\mathbf H$. This generalizes Henckell's theorem on decidability of aperiodic pointlikes.

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عنوان ژورنال:
  • CoRR

دوره abs/1801.04638  شماره 

صفحات  -

تاریخ انتشار 2018