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 A255229 #26 Mar 30 2015 10:51:25
%S A255229 5,7,11,13,17,31,41,43,49,77,83,101,109,119,133,179,203,263,277,283,
%T A255229 307,311,329,353,377,407,413,419,431,437,463,473,493,577,581,619,629,
%U A255229 703,757,791,811,907,911,913,991,1001,1037,1061,1103,1121,1249,1289,1337,1373,1441,1457,1487,1523,1597,1651,1781
%N A255229 Integers n such that n^2 - 1 is the difference of the squares of twin primes.
%e A255229 31^2 - 1 = 241^2 - 239^2, and (239, 241) is a twin prime pair, so 31 is in the sequence.
%t A255229 lst={};f[n_]:=Sqrt[Prime[n]^2-NextPrime[Prime[n],-1]^2+1];
%t A255229 Do[If[Prime[n]-NextPrime[Prime[n],-1]==2&&IntegerQ[f[n]],AppendTo[lst,f[n]]],{n,3,10^5}];lst (* _Ivan N. Ianakiev_, Mar 30 2015 *)
%o A255229 (PARI) lista(nn) = {forprime(p=3, nn, q = precprime(p-1); if (((p-q) == 2) && issquare(d=p^2-q^2+1), print1(sqrtint(d), ", ")); ); } \\ _Michel Marcus_, Feb 18 2015
%Y A255229 Cf. A088486 (corresponding lesser twin primes), A111046.
%K A255229 nonn
%O A255229 1,1
%A A255229 _Neri Gionata_, Feb 18 2015