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ISSN 1088-6834(e) ISSN 0894-0347(p)

Williams's conjecture is false for reducible subshifts

Author(s): K. H. Kim; F. W. Roush
Journal: J. Amer. Math. Soc. 5 (1992), 213-215.
MSC: Primary 54H20; Secondary 15A36, 28D20
MathSciNet review: 1130528
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Abstract: We show that for two subshifts of finite type having exactly two irreducible components, strong shift equivalence is not the same as shift equivalence. This refutes the Williams conjecture $[{\text{W}}]$ in the reducible case. The irreducible case remains an open problem.

References:

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