%I #5 Jun 18 2017 22:07:09

%S 6563,6571,6841,2504908961,17961239302561,81359229958561,

%T 664565853958561,2295148179742698933452806561,

%U 628962407176689215723405312006561,43414370923880963682387072385024006561,116346745870073113470947277571643877742200278220800006561

%N Primes of the form k!3 + 3^8, where k!3 is the triple factorial number (A007661).

%H Robert Price, <a href="/A288884/b288884.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=n3+3^8&amp;action=Search">PRP Records.Search for n!3+3^8.</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, 3] + 3^8, {i, 0, 100}], PrimeQ[#]&]

%Y Cf. A264867.

%K nonn

%O 1,1

%A _Robert Price_, Jun 18 2017