20 lines
761 B
Python
20 lines
761 B
Python
''' Let d(n) be defined as the sum of proper divisors of n (numbers less than n which divide evenly into n).
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If d(a) = b and d(b) = a, where a b, then a and b are an amicable pair and each of a and b are called amicable numbers.
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For example, the proper divisors of 220 are 1, 2, 4, 5, 10, 11, 20, 22, 44, 55 and 110; therefore d(220) = 284. The proper divisors of 284 are 1, 2, 4, 71 and 142; so d(284) = 220.
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Evaluate the sum of all the amicable numbers under 10000. '''
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import math
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def ami(x):
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test = 1
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sqr = int(math.ceil(math.sqrt(x)))
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if sqr * sqr == x: test += sqr
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for i in xrange(2, sqr + 1):
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if x % i == 0: test += i + x / i
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return test
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for j in xrange(2, 10000):
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tmp = ami(j)
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if j == ami(tmp) and j != tmp:
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print j, '\t', tmp
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