#include <fstream>

using namespace std;

ifstream in("pairs.in");
ofstream out("pairs.out");
int n, ans, scz, cnt;
int v[100005];
int frec[1000005];
int ciur[1005];
int prime[1005];

void build_ciur()
{
    ciur[0] = ciur[1] = 1;
    for(int i = 2; i<=1000; i++)
    {
        if(ciur[i] == 0)
        {
            cnt++;
            prime[cnt] = i;

            for(int j = 2; i*j<=1000; j++)
            {
                ciur[i * j] = 1;
            }
        }
    }
}

int main()
{
    build_ciur();

    in>>n;
    for(int i = 1; i<=n; i++)
    {
        in>>v[i];

        frec[v[i]]++;
    }

    ans = (n * (n - 1)) / 2;

    for(int i = 2; i<=1000000; i++)
    {
        int x = i;
        int nr = 0;
        int ok = 1;

        for(int k = 1; k <=cnt && prime[k] * prime[k] <= x; k++)
        {
            if(x % prime[k] == 0)
            {
                nr++;

                int put = 0;
                while(x % prime[k] == 0)
                {
                    x /= prime[k];
                    put++;
                }

                if(put > 1)
                {
                    ok = 0;
                    break;
                }
            }
        }

        if(x > 1)
        {
            nr++;
        }

        if(ok == 0)
        {
            continue;
        }

        int rez = 0;
        for(int j = 1; i * j <= 1000000; j++)
        {
            rez += frec[i * j];
        }
        if(rez == 0)
        {
            continue;
        }
        rez = (rez * (rez - 1)) / 2;

        if(nr % 2 == 1)
        {
            scz += rez;
        }
        else
        {
            scz -= rez;
        }
    }

    ans -= scz;

    out<<ans;

    return 0;
}