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 A049491 #23 Sep 08 2022 08:44:58 %S A049491 3,11,23,29,53,71,83,101,113,149,179,239,251,269,281,293,311,359,419, %T A049491 443,449,479,491,503,563,599,641,659,683,701,809,839,863,881,911,941, %U A049491 1103,1109,1151,1163,1193,1301,1319,1361,1439,1451,1481,1493,1499,1571 %N A049491 Numbers k such that k and k+128 are both prime. %H A049491 Vincenzo Librandi, <a href="/A049491/b049491.txt">Table of n, a(n) for n = 1..1000</a> %e A049491 11 and 11+128 = 139 are both prime. %t A049491 Select[Prime[Range[300]],PrimeQ[#+128]&] (* _Harvey P. Dale_, Jan 16 2011 *) %o A049491 (Magma) [n: n in [0..2000] | IsPrime(n) and IsPrime(n+128)]; // _Vincenzo Librandi_, Feb 02 2014 %Y A049491 Cf. A001359, A023200, A023202. %K A049491 nonn,easy %O A049491 1,1 %A A049491 _Labos Elemer_