def truncatable_prime(num):
digit = solutions.get_digits(num)
divisor = 1
while num / divisor:
val = num / divisor
if not solutions.is_prime(val) or val == 1:
return False
val = num % divisor
if val == 1:
return False
elif val > 0 and not solutions.is_prime(val):
return False
divisor *= 10
return True
def sum_of_all_amicable_numbers(limit):
"""
>>> sum_of_all_amicable_numbers(10000)
31626
"""
items = []
for num in range(1, limit):
if num in items or solutions.is_prime(num):
continue
result = get_amicable_pair(num)
if result:
a, b = result
if a not in items:
items.append(a)
if b not in items:
items.append(b)
return sum(items)
def test_is_prime(self):
self.assertFalse(solutions.is_prime(1))
self.assertTrue(solutions.is_prime(2))
self.assertFalse(solutions.is_prime(8))
self.assertTrue(solutions.is_prime(11))
self.assertFalse(solutions.is_prime(-10))
def is_circular_prime(num):
for item in get_circular_digits(num):
if not solutions.is_prime(list_to_num(item)):
return False
return True