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arXiv · 2002.08306

Kolakoski Sequence: Links between Recurrence, Symmetry and Limit Density

Alessandro Della Corte
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Abstract

The Kolakoski sequence $S$ is the unique element of $\left\lbrace 1,2 \right\rbrace^ω$ starting with 1 and coinciding with its own run length encoding. We use the parity of the lengths of particular subclasses of initial words of $S$ as a unifying tool to address the links between the main open questions - recurrence, mirror/reversal invariance and asymptotic density of digits. In particular we prove that recurrence implies reversal invariance, and give sufficient conditions which would imply that the density of 1s is $\frac{1}{2}$.

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Alessandro Della Corte. 2020-09-21. Kolakoski Sequence: Links between Recurrence, Symmetry and Limit Density. https://arxiv.org/abs/2002.08306

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