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%I #22 Jul 12 2024 01:13:47
%S 0,1,3,4,8,33,121,177,190,276,473,484,924,937,1722,2626,4077,4464,6166
%N Numbers k such that 8*k! - 1 is prime.
%C Tested to 4700. - _Robert G. Wilson v_, Sep 27 2010
%C Tested to 5127. - _Jinyuan Wang_, Feb 03 2020
%C Tested to 12000. - _Michael S. Branicky_, Jul 11 2024
%H <a href="/index/Pri#primepop">Index entries for sequences related to numbers of primes of the form k*n!+-1</a>
%t fQ[n_] := PrimeQ[8 n! - 1]; k = 0; lst = {}; While[k < 1501, If[ fQ@k, AppendTo[lst, k]; Print@k]; k++ ]; lst
%o (PARI) is(k) = ispseudoprime(8*k!-1); \\ _Jinyuan Wang_, Feb 03 2020
%Y Cf. A002982, A076133, A076134, A099350, A099351, A180627, A180628, A180630, A180631.
%K nonn,more
%O 1,3
%A _Robert G. Wilson v_, Sep 13 2010
%E a(15)-a(18) from _Robert G. Wilson v_, Sep 27 2010
%E a(19) from _Michael S. Branicky_, May 27 2023