using namespace std;
#ifdef EZ
   #include "./ez/ez.h"
   const string FILE_NAME = "test";
#else
   #include <bits/stdc++.h>
   const string FILE_NAME = "pairs";
#endif
#define mp make_pair
#define ll long long
#define pb push_back
#define fi first
#define se second
#define cin fin
#define cout fout
ifstream fin (FILE_NAME + ".in");
ofstream fout (FILE_NAME + ".out");


const int valMAX = 1e6;

bool fv[valMAX + 1];
int mul[valMAX + 1];
int pin[valMAX + 1];


int main()
{
   int n;   cin >> n;
   for (int i = 1; i <= n; ++i)
   {
      int x;   cin >> x;
      fv[x] = 1;
   }

   for (int d = 1; d <= valMAX; ++d)
      for (int i = d; i <= valMAX; i += d)
         mul[d] += fv[i];


   ll ans = 0;
   for (int d = 2; d <= valMAX; ++d)
   {
      pin[d]++;
      ans += mul[d] * (mul[d]-1LL) / 2 * pin[d];
      for (int i = d*2; i <= valMAX; i += d)
         pin[i] -= pin[d];
   }

   cout << n * (n-1LL) / 2 - ans;
}