A Typical Number is Extremely Non-Normal

Anastasios Stylianou

doi:10.2478/udt-2022-0001

Abstract

Fix a positive integer N ≥ 2. For a real number x ∈ [0, 1] and a digit i ∈ {0, 1,..., N − 1}, let Π_i(x, n) denote the frequency of the digit i among the first nN-adic digits of x. It is well-known that for a typical (in the sense of Baire) x ∈ [0, 1], the sequence of digit frequencies diverges as n →∞. In this paper we show that for any regular linear transformation T there exists a residual set of points x ∈ [0,1] such that the T -averaged version of the sequence (Π_i(x, n))_n also diverges significantly.

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A Typical Number is Extremely Non-Normal

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