IMO ShortList 1999, number theory problem 5
Source: IMO ShortList 1999, number theory problem 5
November 13, 2004
number theorydecimal representationsum of digitsIMO Shortlist
Problem Statement
Let be positive integers such that n is not divisible by 3 and . Prove that there exists a positive integer which is divisible by and the sum of its digits in decimal representation is .