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 A270194 #9 Mar 25 2016 07:47:37 %S A270194 1,2,3,4,5,6,9,7,10,8,12,11,15,16,30,13,17,18,31,14,26,20,34,19,33,23, %T A270194 45,24,48,46,93,21,40,25,49,27,50,47,94,22,41,39,80,29,61,54,99,28,52, %U A270194 53,97,36,68,69,124,37,70,73,154,71,127,141,266,32,65,60,112,38,78,74,155,42,85,75,158,72,133,142,267,35,67,62,113,59 %N A270194 Permutation of natural numbers: a(1) = 1, a(2n) = A269389(1+a(n)), a(2n+1) = A269399(a(n)). %C A270194 This sequence can be represented as a binary tree. Each left hand child is produced as A269389(1+n), and each right hand child as A269399(n), when the parent node contains n: %C A270194 1 %C A270194 ................../ \.................. %C A270194 2 3 %C A270194 4......../ \........5 6......../ \........9 %C A270194 / \ / \ / \ / \ %C A270194 / \ / \ / \ / \ %C A270194 / \ / \ / \ / \ %C A270194 7 10 8 12 11 15 16 30 %C A270194 13 17 18 31 14 26 20 34 19 33 23 45 24 48 46 93 %C A270194 etc. %H A270194 Antti Karttunen, <a href="/A270194/b270194.txt">Table of n, a(n) for n = 1..8192</a> %H A270194 <a href="/index/Per#IntegerPermutation">Index entries for sequences that are permutations of the natural numbers</a> %F A270194 a(1) = 1, a(2n) = A269389(1+a(n)), a(2n+1) = A269399(a(n)). %o A270194 (Scheme, with memoization-macro definec) %o A270194 (definec (A270194 n) (cond ((= 1 n) n) ((even? n) (A269389 (+ 1 (A270194 (/ n 2))))) (else (A269399 (A270194 (/ (- n 1) 2)))))) %Y A270194 Inverse: A270193. %Y A270194 Cf. A269389, A269399. %Y A270194 Similar permutations: A270199, A270202. %K A270194 nonn,tabf %O A270194 1,2 %A A270194 _Antti Karttunen_, Mar 16 2016