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 A023231 #28 Sep 08 2022 08:44:47 %S A023231 2,3,5,23,29,47,53,59,89,107,113,137,179,197,227,233,257,263,293,317, %T A023231 359,389,419,509,557,587,593,599,617,653,659,683,839,857,863,887,947, %U A023231 977,1013,1097,1103,1163,1193,1217,1223,1229,1259,1277,1283,1307,1319,1409 %N A023231 Primes p such that 8*p + 7 is also prime. %H A023231 Vincenzo Librandi, <a href="/A023231/b023231.txt">Table of n, a(n) for n = 1..1000</a> %e A023231 For p = 3, 8*p + 7 = 31; %e A023231 for p = 179, 8*p + 7 = 1439. %p A023231 a := proc (n) if isprime(n) = true and isprime(8*n+7) = true then n else end if end proc: seq(a(n), n = 1 .. 1500); # _Emeric Deutsch_, Dec 30 2008 %t A023231 Select[Prime@Range@500, PrimeQ[8 # + 7] &] (* _Vincenzo Librandi_, May 19 2014 *) %o A023231 (Magma) [n: n in PrimesUpTo(1500) | IsPrime(8*n+7)]; // _Vincenzo Librandi_, Nov 20 2010 %Y A023231 Cf. A139487, A007522. %K A023231 nonn,easy %O A023231 1,1 %A A023231 _David W. Wilson_ %E A023231 Edited by _N. J. A. Sloane_, Mar 11 2009 at the suggestion of _R. J. Mathar_