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 A216538 #12 May 02 2013 13:07:21 %S A216538 2,8,11,13,31,41,47,61,79,313,617,863,1097,4793,5851,7741,12251,13963, %T A216538 35449,36779,44507,89849,140057,148091,202667,387433,443609,574219, %U A216538 631181,651821 %N A216538 Numbers n such that the n-th Lucas number is prime, but cannot be written in the form a^2 + 7*b^2. %H A216538 Blair Kelly, <a href="http://mersennus.net/fibonacci">Factorizations of Fibonacci and Lucas numbers</a> %Y A216538 Cf. A000032, A001606. %K A216538 nonn %O A216538 1,1 %A A216538 _V. Raman_, Sep 08 2012