#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;

void Ciur()
{
    int i;
    long long j;
    for (i=3;i<MMAX;i+=2)
        if (!viz[i])
            for (j=1LL*i*i;j<MMAX;j+=i)
                viz[j]=1;
}

int main()
{
    int i,j,aux,cnt,ok,mx=0;
    fin>>n;Ciur();
    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
    {
        //decomp
        cnt=ok=0;aux=i;
        for (j=2;j*j<=aux && !ok;j++)
            if (!viz[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;
}