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