import java.util.*;
public class Main {
    public static void main(String[] args){
      // 入力
      Scanner sc = new Scanner(System.in);
      int N = sc.nextInt();
      
      // 計算
      Long sum = 0L;
      for(int i = 1; i <= N; i++){
        if(i % 5 != 0 && i % 3 != 0){
          sum += i;
        }
      }
      
      // 出力
      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