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 A049498 #11 Dec 22 2013 07:45:18
%S A049498 163,15667,607093,671353,1457857,5772097,9139453,11170933,13243063,
%T A049498 18116473,19433863,21960577,32380177,52896517,115831753,154146133,
%U A049498 165609217,191489677,361241743,394845313,518774953,613615423,705676717,742403797,786242293,945170293
%N A049498 a(n) and a(n)+4^k are primes at least for k=1,2,3,4,5,6,7,8.
%e A049498 163, 163+4 = 167, 163+16 = 179, 163+64 = 227, 163+256 = 419, 163+1024 = 1187, 163+4096 = 4259, 163+16384 = 16547, 163+65536 = 65699 are all primes; the smallest such a 9-chain of primes is {163, 167, 178, 227, 419, 1187, 4259, 16547, 65699}
%t A049498 With[{c=4^Range[8]},Select[Prime[Range[500000]],And@@PrimeQ[#+c]&]] (* _Harvey P. Dale_, May 22 2012 *)
%Y A049498 Cf. A023200, A049492-A049497, A049499-A049500.
%K A049498 nonn
%O A049498 1,1
%A A049498 _Labos Elemer_
%E A049498 More terms from _Michel Marcus_, Dec 22 2013