#include<cstdio>
using namespace std;
int n,a[100005];
long long sol;
inline int cmmdc(int A, int B)
{
    int R;
    while (B)
        R=A%B, A=B, B=R;
    return A;
}
int main()
{
    int i,j;
    freopen("pairs.in","r",stdin);
    freopen("pairs.out","w",stdout);
    scanf("%d",&n);
    for (i=1;i<=n;++i)
    {
        scanf("%d",&a[i]);
        for (j=1;j<i;++j)
            if (cmmdc(a[i],a[j])==1)
                ++sol;
    }
    printf("%lld\n",sol);
    return 0;
}