#include <bits/stdc++.h>
int main(void) {
  int a[10000], b[10000] = {0}, i, k, n, ans = 0;
  scanf("%d", &n);
  for (i = 0; i < n; i++) {
    scanf("%d", &a[i]);
    for (k = 2; k < a[i] / 2; k++) {
      if (a[i] % k == 0)
        break;
      else
        b[i]++;
    }
    if (b[i] == a[i] - 2 - a[i] / 2) ans++;
  }
  printf("%d\n", ans);
}
