def problem_23():
start_num = 3
factor_sums = [reduce(operator.add, utils.get_divizors(x, True)) for x in xrange(start_num, 28123)]
ab_set = set([i + start_num for i,f_sum in enumerate(factor_sums) if f_sum > i + 3])
ab_sums = set(reduce(operator.add, x) for x in itertools.combinations(ab_set, 2))
ab_sums = ab_sums.union(set([x*2 for x in ab_set]))
answers = set(xrange(28124)).difference(ab_sums)
return reduce(operator.add, answers)
def problem_12():
def get_natural_num_sum(n):
return (n**2 + n)/2
n = 1
while True:
val = len(utils.get_divizors(get_natural_num_sum(n)))
if val > 500:
return get_natural_num_sum(n)
n += 1
def problem_12():
def get_natural_num_sum(n):
return (n**2 + n) / 2
n = 1
while True:
val = len(utils.get_divizors(get_natural_num_sum(n)))
if val > 500:
return get_natural_num_sum(n)
n += 1
def problem_23():
start_num = 3
factor_sums = [
reduce(operator.add, utils.get_divizors(x, True))
for x in xrange(start_num, 28123)
]
ab_set = set([
i + start_num for i, f_sum in enumerate(factor_sums) if f_sum > i + 3
])
ab_sums = set(
reduce(operator.add, x) for x in itertools.combinations(ab_set, 2))
ab_sums = ab_sums.union(set([x * 2 for x in ab_set]))
answers = set(xrange(28124)).difference(ab_sums)
return reduce(operator.add, answers)
def problem_21():
start_num = 3
factors = [utils.get_divizors(x, True) for x in xrange(start_num, 10000)]
factor_sum = [reduce(operator.add, factor) for factor in factors]
# padd to make indexing easier
for i in range(start_num):
factor_sum.insert(0, 0)
amicables = set()
for indx in xrange(start_num, 10000):
if factor_sum[indx] > 9999 or factor_sum[indx] < 0:
continue
if indx == factor_sum[factor_sum[indx]] and indx != factor_sum[indx]:
amicables.update([indx, factor_sum[factor_sum[indx]]])
return reduce(operator.add, amicables)
def problem_21():
start_num = 3
factors = [utils.get_divizors(x, True) for x in xrange(start_num, 10000)]
factor_sum = [reduce(operator.add, factor) for factor in factors]
# padd to make indexing easier
for i in range(start_num):
factor_sum.insert(0, 0)
amicables = set()
for indx in xrange(start_num, 10000):
if factor_sum[indx] > 9999 or factor_sum[indx] < 0:
continue
if indx == factor_sum[factor_sum[indx]] and indx != factor_sum[indx]:
amicables.update([indx, factor_sum[factor_sum[indx]]])
return reduce(operator.add, amicables)