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 A131149 #5 Mar 31 2012 13:21:17 %S A131149 0,1,2,3,4,5,7,8,6,9,10,13,11,12,17,18,20,21,22,16,19,14,15,23,24,25, %T A131149 26,27,35,36,33,28,29,34,30,31,32,45,46,49,50,48,54,55,57,58,59,61,62, %U A131149 63,64,44,47,53,56,60,42,51,37,38,43,52,40,41,39,65,66,68,69,67,70,71 %N A131149 Signature permutation of a Catalan automorphism: row 9 of A122285. %C A131149 Derived from automorphism *A130349 with recursion scheme ENIPS. %H A131149 A. Karttunen, <a href="/A131149/b131149.txt">Table of n, a(n) for n = 0..2055</a> %H A131149 <a href="/index/Per#IntegerPermutationCatAuto">Index entries for signature-permutations of Catalan automorphisms</a> %Y A131149 Inverse: A131150. %K A131149 nonn %O A131149 0,3 %A A131149 _Antti Karttunen_, Jun 20 2007