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Primes of the form k!4+4, where k!4 is the quadruple factorial number (A007662).
1

%I #5 Aug 31 2017 04:45:52

%S 5,7,3469,9949,65839,1514209,5221129,40883539,151412629,44358635479,

%T 16713607661375629,36453104912477522894629,

%U 1027438963906784290227656915629,7419136758370889359733910587728129,4551830726072842264843919206776501006328129

%N Primes of the form k!4+4, where k!4 is the quadruple factorial number (A007662).

%H Robert Price, <a href="/A291687/b291687.txt">Table of n, a(n) for n = 1..18</a>

%H Henri& Renaud Lifchitz, <a href="http://www.primenumbers.net/prptop/searchform.php?form=n4+4&amp;action=Search">PRP Records.Search for n!4+4.</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, 4] + 4, {i, 0, 100}], PrimeQ[#]&]

%Y Cf. A291122.

%K nonn

%O 1,1

%A _Robert Price_, Aug 29 2017