def test_is_pentagonal_number(self):
self.assertTrue(my_module.is_pentagonal_number(145))
self.assertFalse(my_module.is_pentagonal_number(467))
import my_module
differences = []
for a in xrange(1, 3000):
for b in xrange(1, 3000):
if a > b:
if my_module.is_pentagonal_number(my_module.nth_pentagonal_number(a) + my_module.nth_pentagonal_number(b)):
if my_module.is_pentagonal_number(my_module.nth_pentagonal_number(a) - my_module.nth_pentagonal_number(b)):
differences.append(my_module.nth_pentagonal_number(a) - my_module.nth_pentagonal_number(b))
print(max(differences))
