Least periods of factors of infinite words
Currie, James D. ; Saari, Kalle
RAIRO - Theoretical Informatics and Applications - Informatique Théorique et Applications, Tome 43 (2009), p. 165-178 / Harvested from Numdam
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We show that any positive integer is the least period of a factor of the Thue-Morse word. We also characterize the set of least periods of factors of a sturmian word. In particular, the corresponding set for the Fibonacci word is the set of Fibonacci numbers. As a by-product of our results, we give several new proofs and tightenings of well-known properties of sturmian words.

Publié le : 2009-01-01
DOI : https://doi.org/10.1051/ita:2008006
Classification:  68R15 
@article{ITA_2009__43_1_165_0,
     author = {Currie, James D. and Saari, Kalle},
     title = {Least periods of factors of infinite words},
     journal = {RAIRO - Theoretical Informatics and Applications - Informatique Th\'eorique et Applications},
     volume = {43},
     year = {2009},
     pages = {165-178},
     doi = {10.1051/ita:2008006},
     mrnumber = {2483449},
     zbl = {1162.68510},
     language = {en},
     url = {http://dml.mathdoc.fr/item/ITA_2009__43_1_165_0}
}

Currie, James D.; Saari, Kalle. Least periods of factors of infinite words. RAIRO - Theoretical Informatics and Applications - Informatique Théorique et Applications, Tome 43 (2009) pp. 165-178. doi : 10.1051/ita:2008006. http://gdmltest.u-ga.fr/item/ITA_2009__43_1_165_0/

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