# 2017 AIME I Problems/Problem 3

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We see that $d(n)$ appears in cycles of $20$, adding a total of $70$ each cycle. Since $\lfloor\frac{2017}{20}\rfloor=100$, we know that by $2017$, there have been $100$ cycles, or $7000$ has been added. This can be discarded, as we're just looking for the last three digits. Adding up the first $17$ of the cycle of $20$, we get that the answer is $\boxed{069}$.