#include <bits/stdc++.h>

using namespace std;

const int MAX_N = 1000005;

int n;

int arr[MAX_N];
int fr[MAX_N];

int sieve[MAX_N];
bitset < MAX_N > ok;

int main() {
  freopen("pairs.in", "r", stdin);
  freopen("pairs.out", "w", stdout);
  scanf("%d", &n);
  sieve[1] = sieve[0] = 1;
  for (int i = 2; i < MAX_N; ++i) {
    if (sieve[i] == 0) {
      for (int j = i; j < MAX_N; j += i) {
        if (j % (i * i) == 0) {
          ok[j] = true;
        }
        ++sieve[j];
      }
    }
  }
  int maxValue = 0;
  for (int i = 1; i <= n; ++i) {
    scanf("%d", &arr[i]);
    maxValue = max(maxValue, arr[i]);
    fr[arr[i]] = 1;
  }
  long long ans = 0;
  for (int i = 2; i < maxValue + 1; ++i) {
    if (ok[i] > 0) {
      continue;
    }
    int cnt = 0;
    for (int j = i; j < maxValue + 1; j += i) {
      cnt += fr[j];
    }
    if (sieve[i] % 2 > 0) {
      ans = 1LL * ans + 1LL * cnt * (cnt - 1) / 2;
    } else {
      ans = 1LL * ans - 1LL * cnt * (cnt - 1) / 2;
    }
  }
  printf("%lld", n * (n - 1) / 2 - ans);
  return 0;
}