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MathNet 2008-part-01 — 165 problems (EN–VI) Question 68

Math Olympiad Vault · MathNet 2008-part-01 — 165 problems (EN–VI)

Question 68

A positive integer is *dapper* if at least one of its multiples begins with $2008$. For example, $7$ is dapper because $200858$ is a multiple of $7$ and begins with $2008$. Observe that $200858 = 28694 \times 7$.
Prove that every positive integer is dapper.