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28 lines
700 B
Python
28 lines
700 B
Python
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from e007 import is_prime
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from e012 import factor
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MIN = 2
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MAX = 10000
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def proper_divisors(n):
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"""Returns the proper divisors of n
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Proper divisors are defined as numbers less than n which divide evenly into n
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"""
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divisors = factor(n)
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# Knock off the last factor, since it is equal to n
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return divisors[:-1]
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sums = {}
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amicable = []
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i = MIN
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while i < MAX:
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if not is_prime(i):
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s = sum(proper_divisors(i))
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sums[i] = s
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if s in sums and i == sums[s] and i != s:
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print i, s, sums[s]
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amicable.append(i)
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amicable.append(s)
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i = i + 1
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print 'Sum of amicable numbers less than {0}: {1}'.format(MAX, sum(amicable))
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