import java.util.Scanner;

public class Main {


	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);

		long N = sc.nextInt();

		String FizzBuzz = "";
		long SUM = 0;


		for(int i = 1; i <= N; i++) {

			if(i % 3 ==0 && i % 5 ==0) {
				FizzBuzz = "FizzBuzz";
			}
			else if(i % 3 ==0) {
				FizzBuzz = "FiZZ";
			}else if(i % 5 ==0) {
				FizzBuzz = "Buzz";
			}
			if(i%3 !=0 && i % 5 !=0) {
				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