2013-06-05 21:47:54 +00:00
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#lang racket
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2016-12-05 22:15:40 +01:00
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(require math)
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2013-06-05 21:47:54 +00:00
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2016-12-05 22:15:40 +01:00
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(define (perfect? n)
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(=
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(* n 2)
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(sum (divisors n))))
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2013-06-05 21:47:54 +00:00
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2016-12-05 22:15:40 +01:00
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; filtering to only even numbers for better performance
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(filter perfect? (filter even? (range 1e5)))
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;-> '(0 6 28 496 8128)
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