import java.util.Scanner;
public class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        int n = scanner.nextInt();
        int count = 0;
        int y = 0;
        for (int j = 0; j < n; j++) {
        	int z = 0;
            int x = scanner.nextInt();
            if (x == 2) {
                count += 1;
            } else if (x % 2 == 1) {
                for (int i = x - 1; i > 2; i--) {
                    y = x % i;
                    if (y == 0) {
                        z += 1;
                        break;
                    }
                }
                if (z == 0) {
                    count += 1;
                     
                }
            }
        }
        System.out.println(count);
    }
}
