#include <bits/stdc++.h>
using namespace std;
ifstream fin("pairs.in");
ofstream fout("pairs.out");
#define int long long
const int NMAX = 1e6 + 5;
int freq[NMAX], vmax, n, dp[NMAX];

signed main()
{
    fin >> n;
    for(int i = 1; i <= n; i ++)
    {
        int val;
        fin >> val;
        freq[val]++;
        vmax = max(vmax, val);
    }

    for(int i = vmax; i >= 1; i--)
    {
        for(int j = i; j <= vmax; j += i)
            dp[i] += freq[j];

        dp[i] = dp[i] * (dp[i] - 1) / 2;
        for(int j = 2 * i; j <= vmax; j += i)
            dp[i] -= dp[j];
    }
    fout << dp[1];

    return 0;
}