def abundant(x):
return sum(euler_util.proper_divisors(x)) > x
# amicable numbers
# sums[a] == b
# sums[b] == a
import euler_util
sums = [0] + [sum(euler_util.proper_divisors(i)) for i in range(1,10000)]
amicable = set()
for a in range(1,10000):
b = sums[a]
if b == a:
continue
if b < 10000:
if sums[b] == a:
amicable.add(a)
amicable.add(b)
else:
s = sum(euler_util.proper_divisors(b))
if s == a:
amicable.add(a)
print sum(amicable)