import java.util.*;
import java.lang.*;
import java.io.*;

public class Main {

    public static void main(String[] args) {

      Scanner sc = new Scanner(System.in);
      
      int n = sc.nextInt();
      long sum = 0;

      for(int i=1; i<=n; i++){
        if(i%3==0)
          continue;
        else if(i%5==0)
          continue;
        else
          sum+=i;
      }
      System.out.println(sum);

      sc.close();
   }
}
/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