def test_cataldi(self):
     self.assertEqual(True, solution(524287))
 def test_smallest(self):
     self.assertEqual(True, solution(2))
 def test_provided_3(self):
     self.assertEqual(True, solution(7))
 def test_negative(self):
     self.assertEqual(False, solution(-3))
 def test_provided_1(self):
     self.assertEqual(False, solution(12))