7 lines
328 B
Common Lisp
7 lines
328 B
Common Lisp
(loop for candidate from 2 below (expt 2 19)
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for sum = (+ (/ candidate)
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(loop for factor from 2 to (isqrt candidate)
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when (zerop (mod candidate factor))
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sum (+ (/ factor) (/ (floor candidate factor)))))
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when (= sum 1)
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collect candidate)
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