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 A124518 #17 Oct 31 2019 12:02:54
%S A124518 3,6,15,18,24,27,42,57,60,66,81,102,105,123,129,132,162,195,213,231,
%T A124518 234,255,273,279,297,300,312,330,333,336,339,354,393,402,405,423,426,
%U A124518 465,480,501,510,528,552,564,585,588,609,627,630,636,645,657,666,669,678
%N A124518 Numbers k such that 10k-1 and 10k+1 are twin primes.
%C A124518 All terms are divisible by 3. - _Robert Israel_, Apr 07 2019
%H A124518 Robert Israel, <a href="/A124518/b124518.txt">Table of n, a(n) for n = 1..10000</a>
%p A124518 select(t -> isprime(10*t+1) and isprime(10*t-1), [seq(i,i=3..1000,3)]); # _Robert Israel_, Apr 07 2019
%t A124518 Select[Range[678], And @@ PrimeQ[{-1, 1} + 10# ] &] (* _Ray Chandler_, Nov 16 2006 *)
%Y A124518 Cf. A040040, A045753, A002822, A124065, A124519-A124522, A063983.
%K A124518 nonn
%O A124518 1,1
%A A124518 _Artur Jasinski_, Nov 04 2006