20 lines
491 B
Text
20 lines
491 B
Text
(lib 'math)
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(define (semi-prime? n)
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(= (length (prime-factors n)) 2))
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(for ((i 100))
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(when (semi-prime? i) (write i)))
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4 6 9 10 14 15 21 22 25 26 33 34 35 38 39 46 49 51 55 57 58 62 65 69 74 77 82 85 86 87 91 93 94 95
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(lib 'bigint)
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(define N (* (random-prime 10000000) (random-prime 10000000)))
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→ 6764578882969
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(semi-prime? N)
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→ #t
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;; a pair n,n+1 of semi-primes
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(prime-factors 100000000041)
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→ (3 33333333347)
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(prime-factors 100000000042)
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→ (2 50000000021)
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