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 A143694 #5 Mar 30 2012 18:51:00 %S A143694 1,2,3,4,5,6,10,9,8,7,14,11,15,12,16,13,20,24,19,21,18,22,25,17,26,23, %T A143694 30,34,38,29,33,35,28,32,36,27,39,31,40,37,44,48,41,54,56,42,58,47,46, %U A143694 51,50,55,57,52,43,45,60,49,59,53,61,62,68,64,66,72,74,78,63,67,84,86 %N A143694 A143692(A143692(n)). %C A143694 Permutation of the natural numbers with inverse A143693. %H A143694 <a href="/index/Per#IntegerPermutation">Indexentries for sequences that are permutations of the natural numbers</a> %Y A143694 A143691. %K A143694 nonn %O A143694 1,2 %A A143694 _Reinhard Zumkeller_, Aug 29 2008