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Decidability, arithmetic subsequences and eigenvalues of morphic subshifts

102   0   0.0 ( 0 )
 Added by Fabien Durand
 Publication date 2018
and research's language is English
 Authors Fabien Durand




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We prove decidability results on the existence of constant subsequences of uniformly recurrent morphic sequences along arithmetic progressions. We use spectral properties of the subshifts they generate to give a first algorithm deciding whether, given p $in$ N, there exists such a constant subsequence along an arithmetic progression of common difference p. In the special case of uniformly recurrent automatic sequences we explicitely describe the sets of such p by means of automata.



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