Complexity of Conjugacy, Factoring and Embedding for Countable Sofic Shifts of Rank 2

@inproceedings{Salo2014ComplexityOC,
  title={Complexity of Conjugacy, Factoring and Embedding for Countable Sofic Shifts of Rank 2},
  author={Ville Salo and Ilkka T{\"o}rm{\"a}},
  booktitle={Automata},
  year={2014}
}
In this article, we study countable sofic shifts of Cantor-Bendixson rank at most 2. We prove that their conjugacy problem is complete for \(\mathsf {GI}\), the complexity class of graph isomorphism, and that the existence problems of block maps, factor maps and embeddings are \(\mathsf {NP}\)-complete. 
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