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 A087681 #13 Jan 26 2019 14:02:36
%S A087681 11,13,17,23,25,35,37,47,53,65,67,73,77,95,103,107,133,143,145,157,
%T A087681 173,185,187,205,217,233,235,245,257,263,275,277,287,343,353,373,395,
%U A087681 403,415,425,427,437,455,473,485,493,497,515,563,593,607,613,625,637,647
%N A087681 Numbers n such that n + 6 and n - 6 are both prime.
%C A087681 Many terms are of the form 5 + n + n^2 or 5 + 2*n^2: A054794.
%H A087681 Harvey P. Dale, <a href="/A087681/b087681.txt">Table of n, a(n) for n = 1..1000</a>
%t A087681 f[n_]:=PrimeQ[n-6]&&PrimeQ[n+6]; lst={}; Do[If[f[n],AppendTo[lst,n]],{n,2,7!,1}]; lst (* _Vladimir Joseph Stephan Orlovsky_, Aug 12 2009 *)
%t A087681 Select[Range[2,700],AllTrue[#+{6,-6},PrimeQ]&] (* The program uses the AllTrue function from Mathematica version 10 *) (* _Harvey P. Dale_, Jan 26 2019 *)
%Y A087681 Cf. A054794.
%Y A087681 Cf. A014574, A087678-A087683, A087695-A087697, A088766.
%K A087681 easy,nonn
%O A087681 1,1
%A A087681 _Zak Seidov_, Sep 27 2003