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 A074682 #6 Oct 15 2015 10:55:23 %S A074682 0,1,3,2,8,7,4,6,5,22,21,17,20,18,10,9,14,19,16,11,12,15,13,64,63,58, %T A074682 62,59,46,45,54,61,57,48,49,55,50,27,26,23,25,24,38,37,51,60,56,42,44, %U A074682 53,47,29,28,30,32,31,39,40,52,43,33,34,35,41,36,196,195,189,194,190 %N A074682 Permutation of natural numbers induced by the Catalan bijection gmA074682! acting on the parenthesizations encoded by A014486/A063171. %H A074682 A. Karttunen, <a href="http://www.iki.fi/~kartturi/matikka/Nekomorphisms/gatomorf.htm">Gatomorphisms</a> (with the complete Scheme source) %H A074682 <a href="/index/Per#IntegerPermutation">Index entries for sequences that are permutations of the natural numbers</a> %o A074682 (Scheme function implementing this automorphism on list-structures:) %o A074682 (define (gmA074682! s) (cond ((pair? s) (gmA074682! (car s)) (gmA074682! (cdr s)) (gmrobr! s))) s) %Y A074682 Inverse of A074681. a(n) = A057163(A074683(A057163(n))). Occurs in A073200. %K A074682 nonn %O A074682 0,3 %A A074682 _Antti Karttunen_, Sep 11 2002