import java.util.Date;
import java.util.Scanner;
public class Main{
	public static void main(String[] args){
		long exec_time=new Date().getTime();
		Scanner sc=new Scanner(System.in);
		long n=sc.nextLong();
		int ans=0;
		for(long i=1;i<=n;i++){
			if(i%3==0&&i%5==0){
				ans+=4;
			}else if(i%3==0){
				ans+=2;
			}else if(i%5==0){
				ans+=2;
			}
		}
		System.out.println(ans);
		System.err.println(new Date().getTime()-exec_time+"ans");
	}
}