Abstract
As is well-known, Axel Thue constructed an infinite word over a 3-letter alphabet that contains no squares, that is, no nonempty subwords of the form xx. In this paper we consider a variation on this problem, where we try to avoid approximate squares, that is, subwords of the form xx′ where |x| = |x′| and x and x′ are “nearly” identical.
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Krieger, D., Ochem, P., Rampersad, N., Shallit, J. (2007). Avoiding Approximate Squares. In: Harju, T., Karhumäki, J., Lepistö, A. (eds) Developments in Language Theory. DLT 2007. Lecture Notes in Computer Science, vol 4588. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-540-73208-2_27
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DOI: https://doi.org/10.1007/978-3-540-73208-2_27
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