def main():
    n = int(input())
    nums = range(1, n + 1)
    count = 0

    for num in nums:
        if num % 3 == 0 and num % 5 == 0:
            count += 4
        elif num % 3 == 0:
            count += 2
        elif num % 5 == 0:
            count += 2
    print(count)


if __name__ == "__main__":
    main()