#include <fstream>
#include <algorithm>
using namespace std;
ifstream fin("pairs.in");
ofstream fout("pairs.out");
int n;
int v[100004];
long long f[1000004];
int main(){
    fin >> n;
    for(int i = 1; i <= n; i++){
        fin >> v[i];
        for(int d = 1; d*d <= v[i]; d++){
            if(v[i] % d == 0){
                f[d]++;
                if(d*d < v[i]){
                    f[v[i]/d]++;
                }
            }
        }
    }
    for(int i = 1000000; i >= 1; i--){
        f[i] = (f[i]-1)*f[i]/2;
        for(int j = 2*i; j <= 1000000; j += i){
            f[i] -= f[j];
        }
    }
    fout << f[1];
    return 0;
}