This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A289860 #10 Feb 27 2025 13:34:43
%S A289860 2,3,19,43,229,3463,208843,5221123,151412623,16713607661375623,
%T A289860 1027438963906784290227656915623,7419136758370889359733910587728123,
%U A289860 64138437276116338514899657030909640623,99213846986734491072350087622336908512964418837890623
%N A289860 Primes of the form k!4 - 2, where k!4 is the quadruple factorial number (A007662).
%H A289860 Robert Price, <a href="/A289860/b289860.txt">Table of n, a(n) for n = 1..23</a>
%H A289860 Henri and Renaud Lifchitz, <a href="http://www.primenumbers.net/prptop/searchform.php?form=n4-2&action=Search">PRP Records.Search for n!4-2</a>.
%H A289860 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 A289860 OpenPFGW Project, <a href="http://sourceforge.net/projects/openpfgw/">Primality Tester</a>.
%F A289860 a(n) = A007662(A283554(n)) - 2. - _Elmo R. Oliveira_, Feb 25 2025
%t A289860 MultiFactorial[n_, k_] := If[n<1, 1, n*MultiFactorial[n-k, k]];
%t A289860 Select[Table[MultiFactorial[i, 4] - 2, {i, 3, 100}], PrimeQ[#]&]
%Y A289860 Cf. A007662, A283554.
%K A289860 nonn
%O A289860 1,1
%A A289860 _Robert Price_, Jul 13 2017