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Primes of the form k!8-2, where k!8 is the octuple factorial number (A114800).
1

%I #6 Jul 12 2017 10:15:56

%S 2,3,5,7,31,103,151,3823,16927,126223,137227543,76663738303,

%T 475493443423,1132114642884223,232032717002861773,494437513909964623,

%U 8949366251999798623,22043108115271868623,30822262564469609858623,29990243754746489604765373

%N Primes of the form k!8-2, where k!8 is the octuple factorial number (A114800).

%H Robert Price, <a href="/A289759/b289759.txt">Table of n, a(n) for n = 1..32</a>

%H Henri & Renaud Lifchitz, <a href="http://www.primenumbers.net/prptop/searchform.php?form=n8-2&amp;action=Search">PRP Records.Search for n!8-2.</a>

%H Joe McLean, <a href="http://web.archive.org/web/20091027034731/http://uk.geocities.com/nassarawa%40btinternet.com/probprim2.htm">Interesting Sources of Probable Primes</a>

%H OpenPFGW Project, <a href="http://sourceforge.net/projects/openpfgw/">Primality Tester</a>

%t MultiFactorial[n_, k_] := If[n<1, 1, n*MultiFactorial[n-k, k]];

%t Select[Table[MultiFactorial[i, 8] - 2, {i, 3, 100}], PrimeQ[#]&]

%Y Cf. A204664.

%K nonn

%O 1,1

%A _Robert Price_, Jul 11 2017