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Primes of the form k!6-8, where k!6 is the sextuple factorial number (A085158).
1

%I #7 Jul 10 2017 22:51:50

%S 19,47,83,397,1721,229627,21827567,295540237,13299311017,678264862267,

%T 3879320022245629336367,817800727933873464057151867,

%U 85869076433056713726000946867,9531467484069295223586105103117,15873007435437477980505511601565617

%N Primes of the form k!6-8, where k!6 is the sextuple factorial number (A085158).

%H Robert Price, <a href="/A289728/b289728.txt">Table of n, a(n) for n = 1..26</a>

%H Henri & Renaud Lifchitz, <a href="http://www.primenumbers.net/prptop/searchform.php?form=n6-8&amp;action=Search">PRP Records.Search for n!6-8.</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, 6] - 8, {i, 8, 100}], PrimeQ[#]&]

%Y Cf. A289686.

%K nonn

%O 1,1

%A _Robert Price_, Jul 10 2017