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#include <fstream>
#include <vector>
using namespace std;
ifstream f("pairs.in");
ofstream g("pairs.out");
const int nmax = 1000005;
int fr[nmax], maxi, n, ans[nmax];
int main()
{
f >> n;
for(int i = 1; i <= n; i ++)
{
int x; f >> x;
fr[x] ++; maxi = max(maxi, x);
}
for(int i = maxi; i >= 1; i --)
{
for(int j = i; j <= maxi; j += i)
ans[i] += fr[j];
ans[i] = (ans[i] + 1) * ans[i] / 2;
for(int j = 2 * i; j <= maxi; j += i)
ans[i] -= ans[j];
}
g << ans[1];
return 0;
}