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 A269388 #7 Mar 03 2016 22:51:45 %S A269388 0,1,2,3,4,5,8,7,6,9,16,11,32,17,10,15,64,13,12,19,14,33,128,23,256, %T A269388 65,18,35,512,21,24,31,22,129,20,27,1024,25,34,39,2048,29,4096,67,30, %U A269388 257,8192,47,28,513,26,131,16384,37,48,71,38,1025,40,43,32768,49,66,63,36,45,65536,259,46,41,131072,55,96,2049,130,51,262144,69,44 %N A269388 Permutation of natural numbers: a(1) = 0, after which, a(2n) = 1 + 2*a(n), a(2n+1) = 2 * a(A269380(n)). %C A269388 Note the indexing: Domain starts from 1, range from 0. %H A269388 Antti Karttunen, <a href="/A269388/b269388.txt">Table of n, a(n) for n = 1..1024</a> %H A269388 <a href="/index/Per#IntegerPermutation">Index entries for sequences that are permutations of the natural numbers</a> %F A269388 a(1) = 0, after which, a(2n) = 1 + 2*a(n), a(2n+1) = 2 * a(A269380(n)). %F A269388 As a composition of other permutations: %F A269388 a(n) = A252754(A269172(n)). %F A269388 a(n) = A269378(A260742(n)). %o A269388 (Scheme, with memoization-macro definec) %o A269388 (definec (A269388 n) (cond ((= 1 n) (- n 1)) ((even? n) (+ 1 (* 2 (A269388 (/ n 2))))) (else (* 2 (A269388 (A269380 n)))))) %Y A269388 Inverse: A269387. %Y A269388 Cf. A269380. %Y A269388 Related permutations: A260742, A269386, A269172. %Y A269388 Cf. also A252754, A269378. %Y A269388 Differs from A156552, A252754 and A246677(n-1) for the first time at n=19, which here a(19)=12, instead of 128. %K A269388 nonn %O A269388 1,3 %A A269388 _Antti Karttunen_, Mar 01 2016