import java.util.Scanner;
public class Main{
 public static void main(String[] args) {
   Scanner kbd = new Scanner(System.in);
   int n =kbd.nextInt();
   long c=0;
   for(int i=1;i<n+1;i++){
     if(i%3!=0&&i%5!=0){
       c=c+i;
     }
   }
   System.out.println(c);
 }
}

/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