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On Critical exponents in fixed pointsof k-uniform binary morphisms

Published online by Cambridge University Press:  20 December 2007

Dalia Krieger
Dalia Krieger*
Affiliation:
School of Computer Science, University of Waterloo, Waterloo, ON N2L 3G1, Canada; d2kriege@cs.uwaterloo.ca
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Abstract

Let w be an infinite fixed point of a binary k-uniform morphism f, and let E w bethe critical exponent of w. We give necessary and sufficient conditions for E w to bebounded, and an explicit formula to compute it when it is. In particular, we show that E wis always rational. We also sketch an extension of our method to non-uniform morphisms over generalalphabets.

Keywords

Critical exponentbinary k-uniform morphism.

Information

Type
Research Article
Information
RAIRO - Theoretical Informatics and Applications , Volume 43 , Issue 1 , January 2009 , pp. 41 - 68
Copyright
© EDP Sciences, 2008

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