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 A338251 #9 Oct 20 2020 19:02:03 %S A338251 0,1,2,3,5,4,8,9,7,6,10,11,13,12,20,21,19,18,14,15,17,16,32,33,31,30, %T A338251 34,35,37,36,28,29,27,26,22,23,25,24,40,41,39,38,42,43,45,44,52,53,51, %U A338251 50,46,47,49,48,80,81,79,78,82,83,85,84,76,77,75,74,70,71 %N A338251 Nonnegative values in A317050, in order of appearance. %C A338251 This sequence is a permutation of the nonnegative integers, with inverse A338253 (the offset has been set to 0 so as to have a permutation). %H A338251 Rémy Sigrist, <a href="/A338251/b338251.txt">Table of n, a(n) for n = 0..5461</a> %H A338251 <a href="/index/Per#IntegerPermutation">Index entries for sequences that are permutations of the natural numbers</a> %F A338251 a(0) = 0. %F A338251 a(n) = A317050(A053738(n)) for any n > 0. %F A338251 a(n) = n iff n belongs to A193652. %e A338251 A338251 = 0, 1, -1, -2, 2, 3, 5, 4, -4, -3, -5, -6, -10, -9, -7, -8, 8, ... %e A338251 We keep: 0, 1, 2, 3, 5, 4, 8, ... %o A338251 (PARI) A317050(n) = fromdigits(binary(bitxor(n, n>>1)), -2) %o A338251 print (select(v -> v>=0, apply(A317050, [0..109]))) %Y A338251 See A338245 and A338248 for similar sequences. %Y A338251 Cf. A053738, A193652, A317050, A338252, A338253. %K A338251 nonn,look,base %O A338251 0,3 %A A338251 _Rémy Sigrist_, Oct 18 2020