def fizz_buzz_count(num: int) -> int:
    result = 0
    for i in range(num):
        if (i+1) % 3 == 0 and (i+1) % 5 == 0:
            result += 4
        elif (i+1) % 3 == 0:
            result += 2
        elif (i+1) % 5 == 0:
            result += 2
        else:
            pass
    return result

print(fizz_buzz_count(int(input())))