P608
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Divisor Sums

ℹ️Published on Saturday, 17th June 2017, 04:00 pm; Solved by 339;
Difficulty rating: 80%

Let $D(m,n)=\displaystyle\sum_{d\mid m}\sum_{k=1}^n\sigma_0(kd)$ where $d$ runs through all divisors of $m$ and $\sigma_0(n)$ is the number of divisors of $n$.
You are given $D(3!,10^2)=3398$ and $D(4!,10^6)=268882292$.

Find $D(200!,10^{12}) \bmod (10^9 + 7)$.



Soluzione

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