#include <bits/stdc++.h>
using namespace std;

ifstream in("pairs.in");
ofstream out("pairs.out");

const int M_MAX = 1000000, N_MAX = 100000;

int n;

int ans;
bool frecv[M_MAX + 2];

int main()
{
    in >> n;
    for(int i = 1; i <= n; i++)
    {
        int x;
        in >> x;
        frecv[x] = true;
    }

    ans = n * (n - 1) / 2;
    for(int i = 2; i <= M_MAX; i++)
    {
        int cnt = 0;
        for(int j = i; j <= M_MAX; j += i)
            cnt += frecv[j];

        ans -= cnt * (cnt - 1) / 2;
    }

    out << ans << '\n';

    return 0;
}