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Search: id:A140293
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| A140293 |
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Numbers n such that n!/n#-1 is prime. |
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+0
1
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| 4, 5, 6, 7, 8, 16, 17, 21, 34, 39, 45, 50, 72, 73, 76, 133, 164
(list; graph; listen)
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OFFSET
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4,1
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FORMULA
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n# is the primorial function.
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EXAMPLE
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7!/7# = 24. 24-1=23,prime.
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PROGRAM
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(PARI) g(n) = for(x=4, n, y=x!/primorial(x)-1; z=nextprime(y+1); if(ispseudoprime(y), print1(x", ")))
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CROSSREFS
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Sequence in context: A050038 A059709 A071623 this_sequence A075341 A143789 A068521
Adjacent sequences: A140290 A140291 A140292 this_sequence A140294 A140295 A140296
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KEYWORD
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nonn
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AUTHOR
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Cino Hilliard (hillcino368(AT)hotmail.com), May 25 2008
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