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arXiv · 1908.07554

Reducing the Sarnak Conjecture to Toeplitz systems

Wen Huang·Zhengxing Lian·Song Shao·Xiangdong Ye
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Abstract

In this paper, we show that for any sequence ${\bf a}=(a_n)_{n\in \Z}\in \{1,\ldots,k\}^\mathbb{Z}$ and any $\epsilon>0$, there exists a Toeplitz sequence ${\bf b}=(b_n)_{n\in \Z}\in \{1,\ldots,k\}^\mathbb{Z}$ such that the entropy $h({\bf b})\leq 2 h({\bf a})$ and $\lim_{N\to\infty}\frac{1}{2N+1}\sum_{n=-N}^N|a_n-b_n|<\epsilon$. As an application of this result, we reduce Sarnak Conjecture to Toeplitz systems, that is, if the M\"{o}bius function is disjoint from any Toeplitz sequence with zero entropy, then the Sarnak conjecture holds.

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Wen Huang, Zhengxing Lian, Song Shao, Xiangdong Ye. 2019-08-20. Reducing the Sarnak Conjecture to Toeplitz systems. https://arxiv.org/abs/1908.07554

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