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MathNet 2014 Question 53

Math Olympiad Vault · MathNet 2014

Question 53

For every positive integer $n$, let $s(n)$ be the sum of its digits. Determine the least positive integer $k$ such that
$$s(k)=s(2k)=s(3k)=\cdots=s(2013k)=s(2014k).$$