International Journal of Mathematics and Mathematical Sciences
Volume 22 (1999), Issue 3, Pages 655-658
doi:10.1155/S0161171299226555

Research notes on a density problem of Erdös

Safwan Akbik

Department of Mathematics, Hofstra University, Hempstead 11550, NY, USA

Abstract

For a positive integer n, let P(n) denotes the largest prime divisor of n and define the set: 𝒮(x)=𝒮={nx:ndoes not divideP(n)!}. Paul Erdös has proposed that |S|=o(x) as x, where |S| is the number of nS. This was proved by Ilias Kastanas. In this paper we will show the stronger result that |S|=O(xe1/4logx).