#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],cnt[MMAX];
long long ans;

int main()
{
    int i,j,mx=0;
    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++)
        {
            if (!cnt[i])
            {
                cnt[i]=1;
                for (j=i+i;j<=mx;j+=i)
                    fr[i]+=fr[j],cnt[j]++;
            }
            else
                for (j=i+i;j<=mx;j+=i)
                    fr[i]+=fr[j];
        }
    for (i=2;i*i<=mx;i++)
        for (j=i*i;j<=mx;j+=i*i)
            cnt[j]=0;

    for (i=2;i<=mx;i++)//propagare
        if (cnt[i]>=1)//e bun
            {
                for (j=i;j<=mx;j+=i)
                    if (cnt[i]&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;
}