English

On Schizophrenic Patterns in b-ary Expansions of Some Irrational Numbers

Number Theory 2020-02-18 v1

Abstract

In this paper we study the bb-ary expansions of the square roots of the function defined by the recurrence fb(n)=bfb(n1)+nf_b(n)=b f_b(n-1)+n with initial value f(0)=0f(0)=0 taken at odd positive integers nn, of which the special case b=10b=10 is often referred to as the "schizophrenic" or "mock-rational" numbers. Defined by Darling in 20042004 and studied in more detail by Brown in 20092009, these irrational numbers have the peculiarity of containing long strings of repeating digits within their decimal expansion. The main contribution of this paper is the extension of schizophrenic numbers to all integer bases b2b\geq2 by formally defining the schizophrenic pattern present in the bb-ary expansion of these numbers and the study of the lengths of the non-repeating and repeating digit sequences that appear within.

Keywords

Cite

@article{arxiv.2002.06584,
  title  = {On Schizophrenic Patterns in b-ary Expansions of Some Irrational Numbers},
  author = {László Tóth},
  journal= {arXiv preprint arXiv:2002.06584},
  year   = {2020}
}