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 A266154 #4 Dec 22 2015 15:15:47 %S A266154 0,1,3,2,5,4,6,7,9,8,10,11,12,13,15,14,17,16,18,19,20,21,23,22,24,25, %T A266154 27,26,29,28,30,31,35,34,36,33,38,37,39,32,40,41,43,42,45,44,46,47,50, %U A266154 49,51,48,53,52,54,55,57,56,58,59,60,61,63,62,67,66,68 %N A266154 Inverse permutation to A266089. %C A266154 a(n) = A266089(n) for n < 32. %H A266154 Reinhard Zumkeller, <a href="/A266154/b266154.txt">Table of n, a(n) for n = 0..10000</a> %o A266154 (Haskell) %o A266154 import Data.List (elemIndex); import Data.Maybe (fromJust) %o A266154 a266154 = fromJust . (`elemIndex` a266089_list) %Y A266154 Cf. A266089. %K A266154 nonn %O A266154 0,3 %A A266154 _Reinhard Zumkeller_, Dec 22 2015