import java.util.*;

public class Exercise37{
  public static void main (String[] args){

    Scanner sc = new Scanner(System.in);

    int num = sc.nextInt();
    int count = 0;

    for (int n = 1; n <= num; n++){
      if (n % 3 == 0 && n % 5 == 0){
        count += 4;
      }else if(n % 3 == 0){
        count += 2;
      }else if(n % 5 == 0){
        count += 2;
      }
    }

    System.out.println(count);
  }
}