Direct Prime Subshifts and Canonical Covers

Johan Kopra

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arXiv · 2105.02529

Direct Prime Subshifts and Canonical Covers

Johan Kopra

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Abstract

We present a new sufficient criterion to prove that a non-sofic half-synchronized subshift is direct prime. The criterion is based on conjugacy invariant properties of Fischer graphs of half-synchronized shifts. We use this criterion to show as a new result that all n-Dyck shifts are direct prime, and we also give new proofs of direct primeness of non-sofic beta-shifts and non-sofic S-gap shifts. We also construct a class of non-sofic synchronized direct prime subshifts which additionally admit reversible cellular automata with all directions sensitive.

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BibTeX RIS

Johan Kopra. 2021-05-06. Direct Prime Subshifts and Canonical Covers. https://arxiv.org/abs/2105.02529

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