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 A124849 #17 Sep 08 2022 08:45:28
%S A124849 0,2,4,8,10,22,32,34,40,44,50,52,58,68,74,88,92,110,122,134,142,160,
%T A124849 164,178,188,208,212,242,250,260,268,272,304,320,334,344,352,370,374,
%U A124849 382,388,398,424,428,440,458,464,472,484,494,508,520,524,538,550,554,572
%N A124849 Numbers k such that 7k + 3 and 3k + 7 are primes.
%C A124849 Intersection of A089033 and A089953.
%H A124849 Harvey P. Dale, <a href="/A124849/b124849.txt">Table of n, a(n) for n = 1..1000</a>
%t A124849 Select[Range[0,600],AllTrue[{7#+3,3#+7},PrimeQ]&] (* The program uses the AllTrue function from Mathematica version 10 *) (* _Harvey P. Dale_, May 27 2018 *)
%o A124849 (Magma) [n: n in [0..1000] | IsPrime(7*n+3) and IsPrime(3*n+7)] // _Vincenzo Librandi_, Mar 26 2010
%Y A124849 Cf. A089033, A089953, A124850.
%K A124849 nonn
%O A124849 1,2
%A A124849 _Zak Seidov_, Nov 10 2006