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 A255976 #16 Mar 19 2015 07:21:52
%S A255976 101107,101113,101149,101173,101197,101281,101293,101347,101359,
%T A255976 101383,101419,101449,101467,101503,101599,101641,101653,101701,
%U A255976 101719,101797,101839,101863,101929,101977,103307,103349,103409,103421,103457,103577,103613
%N A255976 Primes that are the concatenation of two 3-digit primes.
%C A255976 The last term is a(2753)=997991.
%H A255976 Zak Seidov, <a href="/A255976/b255976.txt">Table of n, a(n) for n = 1..2753</a>
%t A255976 Select[1000 First@ # + Last@ # & /@ Permutations[Select[Range[100, 999], PrimeQ], {2}], PrimeQ] (* _Michael De Vlieger_, Mar 13 2015 *)
%Y A255976 A168529 is a subsequence.
%Y A255976 Subsequence of A105184.
%K A255976 base,fini,full,nonn
%O A255976 1,1
%A A255976 _Zak Seidov_, Mar 12 2015