Uniform Distribution Theory
Journal license

Journal

Uniform Distribution Theory


Volume
& Issue

Volume 17, Issue 1


Published
on

November 23, 2021


Pages

71-89


DOI

Article

Products of Integers With Few Nonzero Digits


Authors

Hajime Kaneko Affiliation:
Institute of Mathematics and (2) Research Core for Mathematical Sciences University of Tsukuba 1–1–1, Tennodai, Tsukuba Ibaraki, 305–8571, JAPAN
and Thomas Stoll Affiliation:
Universit´edeLorraineand (2) CNRS Institut ´Elie Cartan de Lorraine UMR 7502 54506 Vandœuvre-l`es-Nancy, FRANCE


Abstract

Let \( s(n) \) be the number of nonzero bits in the binary digital expansion
of the integer \( n \). We study, for fixed \( k,\ell,m \), the Diophantine system

\[
s(ab)=k,\qquad s(a)=\ell,\qquad s(b)=m,
\]

in odd integer variables \( a,b \). When \( k=2 \) or \( k=3 \), we establish a
bound on \( ab \) in terms of \( \ell \) and \( m \). While such a bound does not
exist in the case of \( k=4 \), we give an upper bound for
\( \min(a,b) \) in terms of \( \ell \) and \( m \).


Keywords

sum of digits, digital expansion, factors.


Citation

Kaneko, H. & Stoll, T. (2022). Products of integers with few nonzero digits. Uniform Distribution Theory, 17(1), 71–89. https://doi.org/10.2478/UDT-2022-0006

Published by: Engineering Journals

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