#include<bits/stdc++.h>
using namespace std;

ifstream fin("pairs.in");
ofstream fout("pairs.out");

const int NMAX=100005;
const int MMAX=1000005;

int n,a[NMAX],sol[MMAX],fr[MMAX];
long long ans;
bitset<MMAX>viz;

int main()
{
    int i,cnt,ok,mx=0;
    long long j,aux;
    fin>>n;
    for (i=1;i<=n;i++)
        {
            fin>>a[i];
            fr[a[i]]++;
            mx=max(mx,a[i]);
        }
    for (i=2;i<=mx;i++)
        {
            for (j=i+i;j<=mx;j+=i)
                fr[i]+=fr[j];
        }
    for (i=2;i<=mx;i++)//propagare
    {
        cnt=ok=0;aux=i;
        for (j=2;j*j<=aux && !ok;j++)
            if (aux%j==0)
            {
                cnt++;aux/=j;
                if (aux%j==0) ok=1;
            }
        if (aux>1) cnt++;

        if (ok==0)//e bun
            {
                for (j=i;j<=mx;j+=i)
                    if (cnt&1)
                        sol[j]+=fr[i];
                    else sol[j]-=fr[i];
            }
    }

    for (i=1;i<=n;i++) ans+=n-sol[a[i]];
    ans>>=1;
    fout<<ans<<"\n";
    return 0;
}