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 A167901 #4 Mar 30 2012 18:51:05 %S A167901 1,5,8,4,6,13,3,10,9,11,2,12,7,14,17,25,20,23,18,19,15,24,21,22,16,26, %T A167901 32,33,27,31,28,30,29,34,40,35,38,39,37,36,41,45,49,42,44,48,43,50,47, %U A167901 46,51,55,59,54,63,62,57,52,60,56,58,53,61,64,70,65,68,69,67,66,71,74 %N A167901 A075380(A075380(n)). %C A167901 Permutation of positive integers; %C A167901 a(A075381(n)) = A075381(n); %C A167901 a(A167902(n)) = A167902(a(n)) = A075380(n). %H A167901 <a href="/index/Per#IntegerPermutation">Index entries for sequences that are permutations of the natural numbers</a> %K A167901 nonn %O A167901 1,2 %A A167901 _Reinhard Zumkeller_, Nov 15 2009