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 A180198 #6 Apr 09 2023 23:07:46 %S A180198 0,1,2,3,4,5,6,7,9,8,11,10,12,13,14,15,19,18,17,16,22,23,20,21,25,24, %T A180198 27,26,28,29,30,31,38,39,36,37,35,34,33,32,44,45,46,47,41,40,43,42,51, %U A180198 50,49,48,54,55,52,53,57,56,59,58,60,61,62,63,76,77,78,79,73,72,75,74,70 %N A180198 a(n) = A180200(A180200(n)). %C A180198 Permutation of the natural numbers with inverse A180199; %C A180198 a(A180201(n)) = A180201(a(n)) = A180200(n); %C A180198 a(A075427(n)) = A075427(n). %H A180198 <a href="/index/Per#IntegerPermutation">Index entries for sequences that are permutations of the natural numbers</a> %Y A180198 Cf. A075427, A180199, A180200, A180201. %K A180198 nonn %O A180198 0,3 %A A180198 _Reinhard Zumkeller_, Aug 15 2010