Created
September 14, 2011 22:19
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import math | |
import time | |
import itertools | |
def isAbundant(n): | |
div = [1] | |
for i in range(2,int(math.sqrt(n))+1): | |
if n%i==0: | |
div += [i] if i==n/i else [i,n/i] | |
return True if sum(div)>n else False | |
t1 = time.time() | |
abundantNumbers = [n for n in xrange(1,28124) if isAbundant(n)] | |
t2 = time.time() | |
print "Compiling list of abundant numbers: ",t2-t1,"sec" | |
t1=time.time() | |
abundantSums = set(i[0]+i[1] for i in itertools.combinations_with_replacement(abundantNumbers,2) if i[0]+i[1]<=28123) | |
t2 = time.time() | |
print "Getting all pairs-sums of abundant numbers: ",t2-t1,"sec" | |
t1=time.time() | |
answer = sum(set(range(1,28124)).difference(abundantSums)) | |
t2 = time.time() | |
print "Set difference operation: ",t2-t1,"sec" | |
print "Answer: ",answer | |
#Answer is 4179871 |
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