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 A139452 #7 May 22 2017 10:10:01
%S A139452 6,8,16,27,66,74,168,253,458,1310,2665,2681,2718,2836,4921,7356,11466
%N A139452 Numbers n such that primorial(n)/2 - 256 is prime.
%C A139452 a(18) > 25000. - _Robert Price_, May 22 2017
%t A139452 k = 1; a = {}; Do[k = k*Prime[n]; If[PrimeQ[k - 256]&&k>256, Print[n]; AppendTo[a, n]], {n, 2, 325}]; a
%Y A139452 Cf. A067026, A067027, A139439-A139457, A103514.
%K A139452 nonn
%O A139452 1,1
%A A139452 _Artur Jasinski_, Apr 21 2008
%E A139452 Drop 3,4 and correct program, a(9)-a(14) from _Ray Chandler_, Jun 16 2013
%E A139452 a(15)-a(17) from _Robert Price_, May 22 2017