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A180630
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Numbers k such that 9*k! - 1 is prime.
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8
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2, 3, 12, 15, 16, 25, 30, 38, 59, 82, 114, 168, 172, 175, 213, 229, 251, 302, 311, 554, 2538, 3050, 3363
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OFFSET
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1,1
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COMMENTS
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LINKS
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MATHEMATICA
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fQ[n_] := PrimeQ[9 n! - 1]; k = 0; lst = {}; While[k < 1501, If[ fQ@k, AppendTo[lst, k]; Print@k]; k++ ]; lst
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PROG
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(PARI) is(k) = ispseudoprime(9*k!-1); \\ Jinyuan Wang, Feb 03 2020
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CROSSREFS
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KEYWORD
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nonn,more
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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