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 A081241 #24 May 03 2019 21:42:33 %S A081241 1,2,3,5,4,6,7,11,9,13,8,12,10,14,15,23,19,27,17,25,21,29,16,24,20,28, %T A081241 18,26,22,30,31,47,39,55,35,51,43,59,33,49,41,57,37,53,45,61,32,48,40, %U A081241 56,36,52,44,60,34,50,42,58,38,54,46,62,63,95,79,111,71,103,87,119,67 %N A081241 Position in B of reversal of n-th term of B, where B is the logic-binary sequence, A007931. %C A081241 A self-inverse permutation of the natural numbers; a(n) = n if and only if A007931(n) is a palindrome. %C A081241 The natural numbers written backwards digit-wise in bijective base-2 numeration, and interpreted forwards. - _Harald Korneliussen_, Apr 11 2019 %H A081241 Carl R. White, <a href="/A081241/b081241.txt">Table of n, a(n) for n = 1..16383</a> %H A081241 <a href="/index/Per#IntegerPermutation">Index entries for sequences that are permutations of the natural numbers</a> %e A081241 A007931 = (1,2,11,12,21,22,111,112,121,122,211,...); and (reversal of term #8) = term #11. %Y A081241 Cf. A007931. %K A081241 base,easy,nonn,look %O A081241 1,2 %A A081241 _Clark Kimberling_, Mar 11 2003