Displaying similar documents to “For each α > 2 there is an infinite binary word with critical exponent α .”

The critical exponent of the Arshon words

Dalia Krieger (2010)

RAIRO - Theoretical Informatics and Applications

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Generalizing the results of Thue (for ) [Norske Vid. Selsk. Skr. Mat. Nat. Kl. (1912) 1–67] and of Klepinin and Sukhanov (for ) [Discrete Appl. Math. (2001) 155–169], we prove that for all ≥ 2, the critical exponent of the Arshon word of order is given by (3–2)/(2–2), and this exponent is attained at position 1.

Infinite words containing squares at every position

James Currie, Narad Rampersad (2010)

RAIRO - Theoretical Informatics and Applications

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Richomme asked the following question: what is the infimum of the real numbers > 2 such that there exists an infinite word that avoids -powers but contains arbitrarily large squares beginning at every position? We resolve this question in the case of a binary alphabet by showing that the answer is = 7/3.

Least Periods of Factors of Infinite Words

James D. Currie, Kalle Saari (2008)

RAIRO - Theoretical Informatics and Applications

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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.

Density of Critical Factorizations

Tero Harju, Dirk Nowotka (2010)

RAIRO - Theoretical Informatics and Applications

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We investigate the density of critical factorizations of infinite sequences of words. The density of critical factorizations of a word is the ratio between the number of positions that permit a critical factorization, and the number of all positions of a word. We give a short proof of the Critical Factorization Theorem and show that the maximal number of noncritical positions of a word between two critical ones is less than the period of that word. Therefore, we consider only...