Yet Another GCD Problem

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Given N, you are asked to solve... yet another GCD problem. $\displaystyle\sum_{i=1}^{N}\sum_{j=1}^{N}\sum_{k=1}^{i}\sum_{l=1}^{j}\gcd (k,i)\gcd(l,j)\gcd(i,j)$ Output the value of this summation modulo $1000000007$ ### Input Input consists of a single integer $N$. ### Output Output the value of the summation modulo 1000000007. ### Constraints $1 \leq N \leq 10^6$ ### Subtasks - 30 points : $

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solution.cppC++17

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