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A076679
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Numbers k such that 3*k! + 1 is prime.
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9
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2, 3, 4, 6, 7, 9, 10, 13, 23, 25, 32, 38, 40, 47, 96, 3442, 4048, 4522, 4887, 7033, 9528, 12915, 31762
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OFFSET
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1,1
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COMMENTS
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a(24) > 50000. - Roger Karpin, Nov 13 2016
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LINKS
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Table of n, a(n) for n=1..23.
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EXAMPLE
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k = 6 is here because 3*6! + 1 = 2161 is prime.
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PROG
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(PARI) isok(n) = isprime(3*n! + 1); \\ Michel Marcus, Nov 13 2016
(PFGW) ABC2 3*$a!+1
a: from 1 to 1000 // Jinyuan Wang, Feb 05 2020
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CROSSREFS
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Cf. A002981, A051915, A076680, A076681, A076682, A076683, A178488, A180626, A126896.
Sequence in context: A088572 A071689 A187092 * A339509 A060233 A235203
Adjacent sequences: A076676 A076677 A076678 * A076680 A076681 A076682
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KEYWORD
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nonn,more
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AUTHOR
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Phillip L. Poplin (plpoplin(AT)bellsouth.net), Oct 25 2002
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EXTENSIONS
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More terms from Serge Batalov, Feb 18 2015
a(20)-a(23) from Roger Karpin, Nov 13 2016
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STATUS
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approved
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