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arXiv · 1907.06626

On the complexity function for sequences which are not uniformly recurrent

Nic Ormes·Ronnie Pavlov
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Abstract

We prove that every non-minimal transitive subshift $X$ satisfying a mild aperiodicity condition satisfies $\limsup c_n(X) - 1.5n = \infty$, and give a class of examples which shows that the threshold of $1.5n$ cannot be increased. As a corollary, we show that any transitive $X$ satisfying $\limsup c_n(X) - n = \infty$ and $\limsup c_n(X) - 1.5n < \infty$ must be minimal. We also prove some restrictions on the structure of transitive non-minimal $X$ satisfying $\liminf c_n(X) - 2n = -\infty$, which imply unique ergodicity (for a periodic measure) as a corollary, which extends a result of Boshernitzan from the minimal case to the more general transitive case.

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Nic Ormes, Ronnie Pavlov. 2019-07-15. On the complexity function for sequences which are not uniformly recurrent. https://arxiv.org/abs/1907.06626

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