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%I #25 Apr 12 2022 12:55:48
%S 0,1,2,4,6,28,30,46,60,72,86,90,112,154,162,206,280,354,400,512,606,
%T 614,678,790,938,1054,1092,1148,1582,1788,2088,2206,2598,2912,3672,
%U 4642,6272,6428,7084,7604,8580,9464,12762,18386,24910,30448,31696,40288,41682,45730
%N Numbers n such that n!8+1 is prime (for n!8 see A114800).
%C n!8 = A114800(n).
%C No other terms < 50000. - _Robert Price_, Jul 29 2012
%H Ken Davis, <a href="http://mfprimes.free-dc.org">Status of Search for Multifactorial Primes</a>.
%H Ken Davis, <a href="http://mfprimes.free-dc.org/mfdata/f08p.html">Results for n!8+1.</a>
%t MultiFactorial[n_, k_] := If[n < 1, 1, n*MultiFactorial[n - k, k]];
%t Select[Range[0, 1000], PrimeQ[MultiFactorial[#, 8] + 1] & ] (* _Robert Price_, Apr 19 2019 *)
%t Select[Range[0,46000],PrimeQ[Times@@Range[#,1,-8]+1]&] (* _Harvey P. Dale_, Apr 12 2022 *)
%o (PARI) for(n=0,9999,isprime(prod(i=0,(n-2)\8,n-8*i)+1)& print1(n","))
%Y Cf. A204657, A204658, A204659, A204660, A204662, A204663, A204664, A156165, A156167, A085150, A085148, A085146, A037083, A080778, A002981.
%K nonn,hard
%O 1,3
%A _M. F. Hasler_, Jan 17 2012
%E a(35)-a(50) from _Robert Price_, Jul 29 2012
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