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 A266411 #9 Jan 02 2016 04:14:43
%S A266411 1,2,4,3,6,8,7,5,10,12,14,13,16,15,11,9,18,20,22,24,23,26,28,27,30,29,
%T A266411 25,32,31,21,19,17,34,36,38,40,42,41,44,46,48,47,50,52,51,54,53,49,56,
%U A266411 58,57,60,59,55,62,61,45,43,64,63,39,37,35,33,66,68,70,72,74,76,75,78,80,82,84,83,86,88,90,89,92,94,93,96,95,91
%N A266411 a(1) = 1, after which each a(n) = (A004074(n)+1)-th number selected from those not yet in the sequence.
%H A266411 Antti Karttunen, <a href="/A266411/b266411.txt">Table of n, a(n) for n = 1..8192</a>
%H A266411 <a href="/index/Ho#Hofstadter">Index entries for Hofstadter-type sequences</a>
%H A266411 <a href="/index/Per#IntegerPermutation">Index entries for sequences that are permutations of the natural numbers</a>
%t A266411 f[n_] := Block[{a = {1}, g, b = Range[2, n]}, g[1] = g[2] = 1; g[x_] := g[x] = g[g[x - 1]] + g[x - g[x - 1]]; Do[{AppendTo[a, #[[1, 1]]], Set[b, Last@ #]} &@ If[# > Length@ b, Break[], TakeDrop[b, {#}]] &@ (2 g[#] - # + 1) &@ k, {k, 2, n}]; a]; f@ 97 (* _Michael De Vlieger_, Dec 29 2015, Version 10.2, based on _Harvey P. Dale_ at A004074 *)
%o A266411 (Scheme, with defineperm1-macro from Antti Karttunen's IntSeq-library)
%o A266411 (defineperm1 (A266411 n) (if (<= n 1) n (let loop ((i 1) (the-nth-one (A004074 n))) (cond ((not-lte? (A266412 i) n) (if (zero? the-nth-one) i (loop (+ i 1) (- the-nth-one 1)))) (else (loop (+ i 1) the-nth-one))))))
%o A266411 (define (A266412 n) (A266411 (- n))) ;; This returns inverse values of A266411 from its hidden cache that defineperm1-macro has prepared. #f is returned for those n that have not yet been encountered.
%o A266411 ;; We consider a > b (i.e. not less than b) also in case a is #f.
%o A266411 ;; (Because of the stateful caching system used by defineperm1-macro):
%o A266411 (define (not-lte? a b) (cond ((not (number? a)) #t) (else (> a b))))
%Y A266411 Inverse: A266412.
%Y A266411 Cf. A004074.
%Y A266411 Similar permutations in Quetian style: A119435, A126917, A246165, A266413.
%Y A266411 Cf. also A265901, A265903.
%K A266411 nonn
%O A266411 1,2
%A A266411 _Antti Karttunen_, Dec 29 2015