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 A142821 #11 Sep 08 2022 08:45:37
%S A142821 23,389,877,1487,1609,2341,2707,4049,4903,5147,5879,6367,6733,6977,
%T A142821 8563,8807,8929,9173,9539,9661,10271,11003,11369,11491,12101,12589,
%U A142821 13687,13931,14419,15761,16127,16249,16493,16981,17713,17957,19421,19543,20641,21617
%N A142821 Primes congruent to 23 mod 61.
%H A142821 Vincenzo Librandi, <a href="/A142821/b142821.txt">Table of n, a(n) for n = 1..1000</a>
%F A142821 a(n) ~ 60n log n. - _Charles R Greathouse IV_, Jul 03 2016
%t A142821 Select[Prime[Range[2700]], MemberQ[{23}, Mod[#, 61]] &] (* _Vincenzo Librandi_, Sep 05 2012 *)
%t A142821 Select[Range[23,22000,61],PrimeQ] (* _Harvey P. Dale_, Jun 17 2018 *)
%o A142821 (Magma) [p: p in PrimesUpTo(22000) | p mod 61 eq 23 ] ; // _Vincenzo Librandi_, Sep 05 2012
%o A142821 (PARI) is(n)=isprime(n) && n%61==23 \\ _Charles R Greathouse IV_, Jul 03 2016
%Y A142821 Cf. A000040.
%K A142821 nonn,easy
%O A142821 1,1
%A A142821 _N. J. A. Sloane_, Jul 11 2008