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