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 A142291 #11 Sep 08 2022 08:45:36
%S A142291 257,601,773,859,1031,1117,1289,2063,2579,2837,3181,3697,4127,4643,
%T A142291 4729,4987,5417,5503,6277,6449,6793,7309,7481,8513,8599,9029,9631,
%U A142291 9803,10061,10663,11093,11351,11437,11867,11953,12211,12641,12899,13759,13931,14447
%N A142291 Primes congruent to 42 mod 43.
%H A142291 Vincenzo Librandi, <a href="/A142291/b142291.txt">Table of n, a(n) for n = 1..1000</a>
%F A142291 a(n) ~ 42n log n. - _Charles R Greathouse IV_, Jul 02 2016
%t A142291 Select[Prime[Range[5000]],MemberQ[{42},Mod[#,43]]&] (* _Vincenzo Librandi_; Aug 25 2012 *)
%t A142291 Select[Range[42,15000,43],PrimeQ] (* _Harvey P. Dale_, Sep 11 2019 *)
%o A142291 (Magma) [p: p in PrimesUpTo(18000) | p mod 43 eq 42 ]; // _Vincenzo Librandi_, Aug 25 2012
%o A142291 (PARI) is(n)=isprime(n) && n%43==42 \\ _Charles R Greathouse IV_, Jul 02 2016
%Y A142291 Cf. A000040.
%K A142291 nonn,easy
%O A142291 1,1
%A A142291 _N. J. A. Sloane_, Jul 11 2008