import java.util.*;

public class Main{
  public static void main(String[] args){
    Scanner scan = new Scanner(System.in);
    long n = scan.nextLong();
    long sum = 0;
    for (int i=1;i<n+1;i++){
      if ((i%3!=0)&&(i%5!=0)){
        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