Abstract
A similarity relation is a relation on words of equal length induced by a symmetric and reflexive relation on letters. The aim of this article is to give an overview of the results concerning repetition-freeness in connection with similarity relations. We consider so called chain relations, cyclic relations and partial words, which can be seen as a special case of similarity relations. As a new result, we prove that local 3 + -repetitions can be avoided in binary partial words and the local avoidability index of \(\mathring{R}\)-cubes is five, where \(\mathring{R}\) is a relation such that the graph of the relation is a cycle.
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Kärki, T. (2013). Similarity Relations and Repetition-Freeness. In: Karhumäki, J., Lepistö, A., Zamboni, L. (eds) Combinatorics on Words. Lecture Notes in Computer Science, vol 8079. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-642-40579-2_19
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DOI: https://doi.org/10.1007/978-3-642-40579-2_19
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