Title
Normal numbers with digit dependencies.
Abstract
We give metric theorems for the property of Borel normality for real numbers under the assumption of digit dependencies in their expansion in a given integer base. We quantify precisely how much digit dependence can be allowed such that almost all real numbers are normal. Our theorem states that almost all real numbers are normal when at least slightly more than log log n consecutive digits with indices starting at position n are independent. As the main application, we consider the Toeplitz set T-P, which is the set of all sequences a(1)a(2)... of symbols from {0,..., b - 1} such that a(n) is equal to apn for every p in P and n = 1, 2,.... Here b is an integer base and P is a finite set of prime numbers. We show that almost every real number whose base b expansion is in T-P is normal to base b. In the case when P is the singleton set {2} we prove that more is true: almost every real number whose base b expansion is in T-P is normal to all integer bases. We also consider the Toeplitz transform which maps the set of all sequences to the set T-P, and we characterize the normal sequences whose Toeplitz transform is normal as well.
Year
DOI
Venue
2018
10.1090/tran/7706
TRANSACTIONS OF THE AMERICAN MATHEMATICAL SOCIETY
Field
DocType
Volume
Normality,Integer,Combinatorics,Finite set,Prime number,Algebra,Toeplitz matrix,Singleton,Real number,Mathematics,Normal number
Journal
372
Issue
ISSN
Citations 
6
0002-9947
0
PageRank 
References 
Authors
0.34
0
3
Name
Order
Citations
PageRank
Christoph Aistleitner1195.17
Verónica Becher212122.89
Olivier Carton338140.97