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 A212276 #9 May 16 2012 12:52:48 %S A212276 2,17,37,15101701 %N A212276 Prime generalized Catalan numbers. %C A212276 A004148(n) for n = 3, 6, 7, 22, no more through 70. Note that Koshy and Salmassi give an elementary proof that the only prime Catalan numbers A000108 are a(2) = 2 and a(3) = 5. %C A212276 The next term, if it exists, has more than 2000 digits. - _Charles R Greathouse IV_, May 13 2012 %F A212276 A004148 INTERSECTION A000040. %Y A212276 Cf. A000040, A000108, A004148, A092840. %K A212276 nonn %O A212276 1,1 %A A212276 _Jonathan Vos Post_, May 13 2012