def main():
    N = int(input())
    count = 0
    for i in range(1, N+1):
        if i % 3 == 0 and i % 5 == 0:
            count += 4
        elif i % 3 == 0 or i % 5 == 0:
            count += 2
    print(count)

if __name__ == '__main__':
    main()