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The equality problem for purely substitutive words. (English) Zbl 1216.68209
Berthé, Valérie (ed.) et al., Combinatorics, automata, and number theory. Cambridge: Cambridge University Press (ISBN 978-0-521-51597-9/hbk). Encyclopedia of Mathematics and its Applications 135, 505-529 (2010).
Summary: The aim of this chapter is to prove the decidability of the equality problem for purely substitutive words. This problem, also known as the D0L $\omega$-equivalence problem, was first solved by {\it K. Culik II} and {\it T. Jarju} [J. Assoc. Comput. Mach. 31, 282--298 (1984; Zbl 0632.68078)]. Our presentation follows the simpler approach given by the author in a previous paper. For the entire collection see [Zbl 1197.68006].

##### MSC:
 68Q45 Formal languages and automata 03B25 Decidability of theories; sets of sentences 37B10 Symbolic dynamics 68-01 Textbooks (computer science)
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