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 A269392 #10 Mar 07 2016 12:30:16 %S A269392 1,2,3,4,5,7,6,8,9,12,10,16,13,15,11,21,14,24,17,32,20,28,18,49,26,38, %T A269392 22,46,25,31,19,64,34,42,23,79,37,53,27,110,48,63,33,94,43,56,29,186, %U A269392 72,87,40,128,57,71,35,174,68,82,39,106,47,60,30,245,92,117,51,152,62,75,36,322,112,127,55,203,77,90,41 %N A269392 Permutation of natural numbers: a(1) = 1, a(2n) = A233271(1+a(n)), a(2n+1) = A269390(a(n)). %C A269392 This sequence can be represented as a binary tree. Each left hand child is produced as A233271(1+n), and each right hand child as A269390(n), when the parent contains n: %C A269392 | %C A269392 ...................1................... %C A269392 2 3 %C A269392 4......../ \........5 7......../ \........6 %C A269392 / \ / \ / \ / \ %C A269392 / \ / \ / \ / \ %C A269392 / \ / \ / \ / \ %C A269392 8 9 12 10 16 13 15 11 %C A269392 21 14 24 17 32 20 28 18 49 26 38 22 46 25 31 19 %C A269392 etc. %H A269392 Antti Karttunen, <a href="/A269392/b269392.txt">Table of n, a(n) for n = 1..3071</a> %H A269392 <a href="/index/Per#IntegerPermutation">Index entries for sequences that are permutations of the natural numbers</a> %F A269392 a(1) = 1, a(2n) = A233271(1+a(n)), a(2n+1) = A269390(a(n)). %F A269392 As a composition of other permutations: %F A269392 a(n) = A269398(A269402(n)). %o A269392 (Scheme, with memoization-macro definec) %o A269392 (definec (A269392 n) (cond ((<= n 1) n) ((even? n) (A233271 (+ 1 (A269392 (/ n 2))))) (else (A269390 (A269392 (/ (- n 1) 2)))))) %Y A269392 Inverse: A269391. %Y A269392 Cf. A233271, A269390. %Y A269392 Cf. also A260432. %Y A269392 Similar or related permutations: A269398, A269402. %K A269392 nonn,base,tabf %O A269392 1,2 %A A269392 _Antti Karttunen_, Mar 05 2016