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 A216509 #7 Sep 10 2012 12:48:46
%S A216509 2,3,5,11,13,17,19,23,29,37,41,43,47,53,59,61,67,71,83,89,101,107,109,
%T A216509 113,131,137,139,149,157,163,167,173,179,181,191,197,211,227,229,233,
%U A216509 239,251,257,263,269,277,281,283,293,307,311,317,331,347,349,353
%N A216509 Primes which cannot be written in the form a^2 + 6*b^2.
%C A216509 These are primes congruent to {5, 11, 13, 17, 19, 23} mod 24.
%Y A216509 Cf. A033199.
%K A216509 nonn
%O A216509 1,1
%A A216509 _V. Raman_, Sep 08 2012