import java.util.Scanner;
public class Main{
    public static void main(String[] args){
        Scanner scan = new Scanner(System.in);
        long N = scan.nextInt();

        //List<String> NList = new ArrayList<String>();
        //int[] Narray = new int[N];
        long sum = 0;

        for(long i=0; i <= N ;i++){
            if(i%3 == 0 || i%5 == 0){
                continue;
            }
            sum += i;
        }
        System.out.println(sum);
    }
}
/tmp/hf-datasets-cache/medium/datasets/42704881117311-config-parquet-and-info-qiankunmu-Project_CodeNet-896c9d36/hub/datasets--qiankunmu--Project_CodeNet_Python800_and_Java250/snapshots/c899fde44a77ba1cc14973ed3de064e4ff3aadc7/Project_CodeNet_Java250.tar.gz