#include <cstdio>

#define dim 100001

int N;
int A[dim];

int prime(int x, int y)
{
    int r;

    while(y)
    {
        r = x % y;
        x = y;
        y = r;
    }

    if(x == 1) return 1;
    return 0;
}

int main()
{
    freopen("pairs.in", "rt", stdin);
    freopen("pairs.out", "wt", stdout);

    int i, j;

    long long r = 0;

    for(scanf("%d", &N), i=1; i<=N; ++i)
        scanf("%d", A+i);

    for(i=1; i<N; ++i)
        for(j=i+1; j<=N; ++j)
            if(prime(A[i], A[j]))
                ++ r;

    printf("%lld", r);

    return 0;
}