N = int(input().strip())

cnt = 0

for i in range(N // 5 + 1):
  for j in range(0, min(i + 1, N - i * 5 + 1)):
    if (N - i * 5 - j * 2) % 3 == 0 and (N - i * 5 - j * 2) >= 0:
      cnt += 1

print(cnt)