def buildChain(seed):
s = list()
m = seed
while not m in s:
if m >= 1000000:
return []
s.append(m)
m = sum(all_factors(m)) - m
s.append(m)
return s
def c_n(n): return sum(all_factors(n))
from helpers import cached_prime, all_factors limit = 10**8 cached_prime(limit + 1) for i in range(2, limit + 1): list(all_factors(i))
def abundent(n):
for i in range(n):
s = sum(all_factors(i)) - i
if i < s:
yield i
from helpers import all_factors, cached_prime, factor
from collections import defaultdict
limit = 10000
visited = defaultdict(bool)
cached_prime(limit * 10)
numbers = []
for i in range(1, limit):
if not visited[i]:
s = sum(all_factors(i)) - i
if i == sum(all_factors(s)) - s:
if i != s:
numbers.append(i)
numbers.append(s)
print (i, s)
visited[i] = True
visited[s] = True
print sum(numbers)