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 A290117 #10 Jul 22 2017 10:08:21
%S A290117 5,29,179,1259,10079,907199,326918591999,1600593426431999,
%T A290117 6463004184721244159999
%N A290117 Primes of the form k! / 4 - 1.
%H A290117 Robert Price, <a href="/A290117/b290117.txt">Table of n, a(n) for n = 1..9</a>
%H A290117 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 A290117 OpenPFGW Project, <a href="http://sourceforge.net/projects/openpfgw/">Primality Tester</a>
%F A290117 a(n) = (A139199(n)!-4)/4.
%t A290117 Select[Table[i! / 4 - 1, {i, 4, 100}], PrimeQ[#]&]
%Y A290117 Cf. A139174, A139199.
%K A290117 nonn
%O A290117 1,1
%A A290117 _Robert Price_, Jul 19 2017