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 A180629 Numbers k such that 8*k! - 1 is prime. 6
 0, 1, 3, 4, 8, 33, 121, 177, 190, 276, 473, 484, 924, 937, 1722, 2626, 4077, 4464 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 COMMENTS Tested to 4700. - Robert G. Wilson v, Sep 27 2010 Tested to 5127. - Jinyuan Wang, Feb 03 2020 LINKS MATHEMATICA fQ[n_] := PrimeQ[8 n! - 1]; k = 0; lst = {}; While[k < 1501, If[ fQ@k, AppendTo[lst, k]; Print@k]; k++ ]; lst PROG (PARI) is(k) = ispseudoprime(8*k!-1); \\ Jinyuan Wang, Feb 03 2020 CROSSREFS Cf. A002982, A076133, A076134, A099350, A099351, A180627, A180628, A180630, A180631. Sequence in context: A168382 A155701 A119529 * A258372 A096847 A011993 Adjacent sequences:  A180626 A180627 A180628 * A180630 A180631 A180632 KEYWORD nonn,more AUTHOR Robert G. Wilson v, Sep 13 2010 EXTENSIONS a(15)-a(18) from Robert G. Wilson v, Sep 27 2010 STATUS approved

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Last modified June 7 04:32 EDT 2020. Contains 334836 sequences. (Running on oeis4.)