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 A082354 #7 Oct 15 2015 10:55:24 %S A082354 0,1,2,3,6,4,5,7,8,14,15,16,9,10,19,11,12,17,18,13,20,21,22,37,38,39, %T A082354 40,41,42,43,44,23,24,47,25,26,27,51,52,53,28,29,56,30,31,45,46,32,48, %U A082354 49,50,60,33,34,54,55,35,57,58,59,36,61,62,63,64,107,108,109,110,111 %N A082354 Permutation of natural numbers induced by the Catalan bijection gma082354 acting on the parenthesizations encoded by A014486/A063171. %H A082354 A. Karttunen, <a href="http://www.iki.fi/~kartturi/matikka/Nekomorphisms/gatomorf.htm">Gatomorphisms</a> (with the complete Scheme source) %H A082354 <a href="/index/Per#IntegerPermutationCatAuto">Index entries for signature-permutations induced by Catalan automorphisms</a> %o A082354 (Scheme functions implementing this automorphism on list-structures:) %o A082354 (define (gma082354! s) (cond ((not (pair? s)) s) ((not (pair? (cdr s))) s) ((not (pair? (cddr s))) (swap! (robl! s))) (else (robl! s)))) %o A082354 (define (robl! s) (let ((ex-car (car s))) (set-car! s (cddr s)) (set-cdr! (cdr s) ex-car) (swap! (cdr s)) (swap! s) s)) %o A082354 (define (swap! s) (let ((ex-car (car s))) (set-car! s (cdr s)) (set-cdr! s ex-car) s)) %Y A082354 Inverse of A082353. a(n) = A057163(A082352(A057163(n))). %K A082354 nonn %O A082354 0,3 %A A082354 _Antti Karttunen_, Apr 17 2003