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 A071669 #28 Jan 19 2024 04:43:56 %S A071669 0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25, %T A071669 26,27,28,29,30,31,32,33,48,35,36,37,38,39,34,41,42,40,44,45,46,43,47, %U A071669 49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70,71 %N A071669 Permutation A057505 applied six times, permutation A071661 cubed, permutation A071663 squared. %C A071669 Inverse permutation: A071670 and also its car/cdr-flipped conjugate. See formulas. %H A071669 Robert Donaghey, <a href="https://doi.org/10.1016/0095-8956(80)90045-3">Automorphisms on Catalan trees and bracketing</a>, J. Combin. Theory, Series B, 29 (1980), 75-90. %H A071669 Antti Karttunen, <a href="http://oeis.org/wiki/User:Antti_Karttunen/Speculations/On_the_fixed_points_of_A071661">On the fixed points of A071661</a>, OEIS Wiki, notes concerning this and related sequences. See especially at the end. %H A071669 Antti Karttunen, <a href="https://web.archive.org/web/20021212104851/http://ndirty.cute.fi/~karttu/matikka/Nekomorphisms/gatomorf.htm">Gatomorphisms</a> (Includes the complete Scheme source for computing this sequence). %H A071669 <a href="/index/Per#IntegerPermutation">Index entries for sequences that are permutations of the natural numbers</a>. %F A071669 a(n) = A057163(A071670(A057163(n))) = A057505(A071667(n)) = A071661(A071661(A071661(n))) = A071663(A071663(n)). %Y A071669 Cf. A057163, A057505, A071661, A071663, A071665, A071667, A071669, A071670. %K A071669 nonn %O A071669 0,3 %A A071669 _Antti Karttunen_, May 30 2002