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 A306229 #18 Feb 11 2019 20:56:45 %S A306229 2,1,4,3,6,5,8,7,10,9,13,14,11,12,16,15,18,17,20,19,22,21,24,23,26,25, %T A306229 28,27,30,29,33,35,31,36,32,34,38,37,40,39,42,41,44,43,46,45,48,47,50, %U A306229 49,53,54,51,52,56,55,58,57,60,59,62,61,64,63,67,68,65 %N A306229 Lexicographically earliest sequence of distinct positive terms such that for any n > 0, K(n) <> K(a(n)) (where K denotes the Kolakoski sequence A000002). %C A306229 This sequence is a self-inverse permutation of the natural numbers. %H A306229 Rémy Sigrist, <a href="/A306229/b306229.txt">Table of n, a(n) for n = 1..1000</a> %H A306229 Rémy Sigrist, <a href="/A306229/a306229.gp.txt">PARI program for A306229</a> %H A306229 <a href="/index/Per#IntegerPermutation">Index entries for sequences that are permutations of the natural numbers</a> %F A306229 a(A013947(n)) = A013948(n). %F A306229 a(A013948(n)) = A013947(n). %F A306229 o(n) = o(a(n)) where o corresponds to the ordinal transform of A000002. %e A306229 The first terms of the sequence, alongside K and its ordinal transform, are: %e A306229 n a(n) K(n) o(n) %e A306229 -- ---- ---- ---- %e A306229 1 2 1 1 %e A306229 2 1 2 1 %e A306229 3 4 2 2 %e A306229 4 3 1 2 %e A306229 5 6 1 3 %e A306229 6 5 2 3 %e A306229 7 8 1 4 %e A306229 8 7 2 4 %e A306229 9 10 2 5 %e A306229 10 9 1 5 %e A306229 11 13 2 6 %e A306229 12 14 2 7 %e A306229 13 11 1 6 %e A306229 14 12 1 7 %e A306229 15 16 2 8 %e A306229 16 15 1 8 %e A306229 17 18 1 9 %e A306229 18 17 2 9 %e A306229 19 20 2 10 %e A306229 20 19 1 10 %o A306229 (PARI) See Links section. %Y A306229 See A306230 for a similar sequence. %Y A306229 Cf. A000002, A013947, A013948. %K A306229 nonn %O A306229 1,1 %A A306229 _Rémy Sigrist_, Jan 30 2019