smallest possible multiple of a no by 1 digit only
Source: 7th Gulf Math Olympiad 2019 GMO p2
December 31, 2019
number theoryDigitsmultiple
Problem Statement
1. Find , the smallest positive multiple of such that all of its digits are either or .
2. Find , the smallest positive multiple of such that all of its digits are either or .
3. How many elements of the set have a positive multiple such that all of its digits are either or ?