English

Uncanny subsequence selections that generate normal numbers

Number Theory 2016-07-14 v1

Abstract

Given a real number 0.a1a2a30.a_1a_2 a_3\dots that is normal to base bb, we examine increasing sequences nin_i so that the number 0.an1an2an30.a_{n_1}a_{n_2}a_{n_3}\dots are normal to base bb. Classically it is known that if the nin_i form an arithmetic progression then this will work. We give several more constructions, including nin_i that are recursively defined based on the digits aia_i. Of particular interest, we show that if a number is normal to base bb, then removing all the digits from its expansion which equal (b1)(b-1) leaves a base-(b1)(b-1) expansion that is normal to base (b1)(b-1).

Keywords

Cite

@article{arxiv.1607.03531,
  title  = {Uncanny subsequence selections that generate normal numbers},
  author = {Joseph Vandehey},
  journal= {arXiv preprint arXiv:1607.03531},
  year   = {2016}
}
R2 v1 2026-06-22T14:52:54.201Z