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 A095261 #6 Mar 30 2012 18:50:44 %S A095261 1,2,3,4,16,10,46,6,5,26,8,39,51,69,17,34,18,9,29,66,40,60,38,25,11, %T A095261 12,21,28,41,64,112,7,130,14,89,67,55,92,71,93,448,91,189,107,85,44, %U A095261 56,48,22,169,50,273,158,54,76,43,133,68,417,134,239,100,288,96,157 %N A095261 A095259(A095259(n)). %C A095261 Integer permutation with inverse A095260: a(A095260(n))=A095260(a(n))=n; %C A095261 A095258(a(n))=a(A095258(n))=A095259(n). %H A095261 <a href="/index/Per#IntegerPermutation">Index entries for sequences that are permutations of the natural numbers</a> %K A095261 nonn %O A095261 1,2 %A A095261 _Reinhard Zumkeller_, May 31 2004