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Core dimension group constraints for factors of sofic shifts

Published online by Cambridge University Press:  19 September 2008

Paul Trow
Department of Mathematical Sciences, Memphis State University, Memphis, Tennessee 38152, USA
Susan Williams
Department of Mathematics and Statistics, University of South Alabama, Mobile, Alabama 36688, USA


We give constraints on the existence of factor maps between sofic shifts. These constraints yield examples of sofic shifts of entropy log n which do not factor onto the full n-shift. We also show that any prime which divides the degree of an endomorphism of a sofic shift must divide the non-leading coefficients of the characteristic polynomial of the core matrix of the shift.

Research Article
Copyright © Cambridge University Press 1993

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