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 A258616 #12 Jun 18 2015 05:59:16
%S A258616 7,9,13,17,25,185,197,261,407,593,1535,2129,2139,2581,4133,4665,15787,
%T A258616 25337,27449
%N A258616 Numbers n such that n!!-16 is prime.
%C A258616 Corresponding primes are 89, 929, 135119, 34459409, ... .
%C A258616 a(20) > 50000.
%H A258616 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>
%t A258616 Select[Range[4,1000],PrimeQ[#!!-16]&] (* _Robert Price_, Jun 05 2015 *)
%t A258616 Do[f=n!! - 16; If[PrimeQ[f], Print[{n, f}]], {n, 4, 600}] (* _Vincenzo Librandi_, Jun 06 2015 *) (see comment)
%Y A258616 Cf. A006882, A007749, A094144, A123910.
%K A258616 hard,more,nonn
%O A258616 1,1
%A A258616 _Robert Price_, Jun 05 2015