import java.util.Scanner;

public class No_311 {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		long endNum = sc.nextLong();
		long z_count = 0;

		for (long l = 1; l <= endNum; l++) {
			if (l % 15 == 0) {
				z_count += 4;
			} else if (l % 5 == 0 || l % 3 == 0) {
				z_count += 2;
			}

		}

		System.out.println(z_count);
		sc.close();

	}

}