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arXiv · 2101.03607

Most numbers are not normal

Andrea Aveni·Paolo Leonetti
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Abstract

We show, from a topological viewpoint, that most numbers are not normal in a strong sense. More precisely, the set of numbers $x \in (0,1]$ with the following property is comeager: for all integers $b\ge 2$ and $k\ge 1$, the sequence of vectors made by the frequencies of all possibile strings of length $k$ in the $b$-adic representation of $x$ has a maximal subset of accumulation points, and each of them is the limit of a subsequence with an index set of nonzero asymptotic density. This extends and provides a streamlined proof of the main result given by Olsen in [Math. Proc. Cambridge Philos. Soc. 137 (2004), 43--53]. We provide analogues in the context of analytic P-ideals and regular matrices.

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Andrea Aveni, Paolo Leonetti. 2021-01-10. Most numbers are not normal. https://doi.org/10.1017/s0305004122000469

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