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arXiv · 2504.18280

Clustering of return words in languages of interval exchanges

Francesco Dolce·Christian B. Hughes
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Abstract

A word over an ordered alphabet is said to be clustering if identical letters appear adjacently in its Burrows-Wheeler transform. Such words are strictly related to (discrete) interval exchange transformations. We use an extended version of the well-known Rauzy induction to show that every return word in the language generated by a regular interval exchange transformation is clustering, partially answering a question of Lapointe (2021).

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Francesco Dolce, Christian B. Hughes. 2025-04-25. Clustering of return words in languages of interval exchanges. https://arxiv.org/abs/2504.18280

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