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 A161996 #11 Dec 16 2017 05:31:55
%S A161996 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,0,1,1,1,0,1,1,1,1,1,1,0,1,1,0,
%T A161996 1,0,1,1,1,1,0,1,1,1,1,1,1,0,1,0,1,1,1,0,1,1,0,1,1,1,1,1,1,1,1,1,1,1,
%U A161996 0,1,0,1,1,1,1,1,1,1,0,1,1,1,1,1,1,0,1,0,0,1,1,0,1,1,1,1,0,1,1,1,1,1,1,0,1
%N A161996 A (negated) characteristic function of twin composite odd numbers.
%C A161996 a(n) = 0 if n is a member of A060461, otherwise a(n) = 1.
%H A161996 Antti Karttunen, <a href="/A161996/b161996.txt">Table of n, a(n) for n = 1..37317</a>
%H A161996 <a href="/index/Ch#char_fns">Index entries for characteristic functions</a>
%t A161996 If[AllTrue[6#+{1,-1},CompositeQ],0,1]&/@Range[300] (* The program uses the AllTrue function from Mathematica version 10 *) (* _Harvey P. Dale_, Feb 15 2015 *)
%o A161996 (PARI) A161996(n) = (isprime((6*n)-1)||isprime((6*n)+1)); \\ _Antti Karttunen_, Dec 15 2017
%Y A161996 Cf. A060461, A100923.
%K A161996 nonn,easy
%O A161996 1,1
%A A161996 _Pierre CAMI_, Jun 24 2009
%E A161996 Definition rephrased by _R. J. Mathar_, Aug 14 2009