A289820 - OEIS

%I #9 Jan 01 2025 13:16:12

%S 37,1106317,17041023757,13106744139423334399757,

%T 111788986826349170054555238399757,

%U 254451773522587035734629406212095999757,12931890526958090978845347074978621685759999757,23265085063150097152411131624511949388385310979653631999999757

%N Primes of the form k!3-243, where k!3 is the triple factorial number (A007661).

%H Harvey P. Dale, <a href="/A289820/b289820.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=n3-243&amp;action=Search">PRP Records.Search for n!3-243.</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] - 243, {i, 10, 100}], PrimeQ[#]&]

%t Select[Table[Times@@Range[n,1,-3]-243,{n,10,150}],PrimeQ] (* _Harvey P. Dale_, Jan 01 2025 *)

%Y Cf. A247465.

%K nonn

%O 1,1

%A _Robert Price_, Jul 12 2017