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 A204764 #9 Aug 11 2014 22:45:47
%S A204764 404851,576791,818723,843911,1053863,1138273,1294849,1467989,1876859,
%T A204764 1964987,1966697,1985077,2030789,2214383,2220553,2423249,2483291,
%U A204764 2527823,2542237,2638087,2680141,2856683,2910329,3106487,3112147,3112519,3175169,3279037,3398761
%N A204764 Primes followed by a gap of 90.
%H A204764 M. F. Hasler, <a href="/A204764/b204764.txt">Table of n, a(n) for n = 1..1000</a>
%H A204764 <a href="/index/Pri#gaps">Index entries for primes, gaps between</a>.
%t A204764 Transpose[Select[Partition[Prime[Range[250000]],2,1],Last[#] - First[#] == 90&]][[1]] (* _Harvey P. Dale_, Jul 31 2012 *)
%o A204764 (PARI) p=0; g=90; for(c=1, 100, while(g+p!=p=nextprime(p+1), ); print1(", "p-g)) \\
%K A204764 nonn
%O A204764 1,1
%A A204764 _M. F. Hasler_, Jan 18 2012