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A080778
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Double factorial primes; values for which n!!+1 is prime.
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24
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OFFSET
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1,3
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COMMENTS
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Numbers n such that A006882(n)+1 is prime.
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LINKS
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Table of n, a(n) for n=1..9.
Ken Davis, Status of Search for Multifactorial Primes.
Ken Davis, Results for n!2+1.
Eric Weisstein's World of Mathematics, Double Factorial Prime
Eric Weisstein's World of Mathematics, Integer Sequence Primes
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CROSSREFS
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Cf. A006882.
Sequence in context: A196290 A182446 A218436 * A007513 A352852 A283756
Adjacent sequences: A080775 A080776 A080777 * A080779 A080780 A080781
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KEYWORD
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hard,nonn
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AUTHOR
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Steven Harvey, Mar 11 2003
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EXTENSIONS
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a(7) from Herman Jamke (hermanjamke(AT)fastmail.fm), Jan 03 2008
a(8) from Sou Fukui, Jun 05 2015
a(9) from Sou Fukui, Jan 17 2017
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STATUS
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approved
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