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 A353661 #11 May 03 2022 17:11:06 %S A353661 0,2,1,4,8,7,3,6,5,10,14,13,18,26,25,17,24,23,9,12,11,16,22,21,15,20, %T A353661 19,28,32,31,36,44,43,35,42,41,48,56,55,64,80,79,63,78,77,47,54,53,62, %U A353661 76,75,61,74,73,27,30,29,34,40,39,33,38,37,46,52,51,60,72 %N A353661 Inverse permutation to A353660. %H A353661 Rémy Sigrist, <a href="/A353661/b353661.txt">Table of n, a(n) for n = 0..6560</a> %H A353661 Rémy Sigrist, <a href="/A353661/a353661.gp.txt">PARI program</a> %H A353661 <a href="/index/Per#IntegerPermutation">Index entries for sequences that are permutations of the natural numbers</a> %F A353661 a(n) < 3^k iff n < 3^k. %e A353661 A353660(7) = 5, so a(5) = 7. %o A353661 (PARI) See Links section. %Y A353661 Cf. A353660. %K A353661 nonn,look,base %O A353661 0,2 %A A353661 _Rémy Sigrist_, May 02 2022