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 A129611 #6 Mar 31 2012 13:21:14 %S A129611 0,1,3,2,7,8,6,4,5,17,18,20,22,21,16,19,14,9,10,15,11,12,13,45,46,48, %T A129611 49,50,54,55,61,63,64,57,62,58,59,44,47,53,60,56,42,51,37,23,24,38,25, %U A129611 26,27,43,52,39,28,29,40,30,31,32,41,33,34,35,36,129,130,132,133,134 %N A129611 Signature-permutation of a Catalan automorphism, row 169 of A089840. %C A129611 Automorphism *A089859 = ENIPS(*A129611). See the definition given in A122204. %H A129611 A. Karttunen, <a href="/A129611/b129611.txt">Table of n, a(n) for n = 0..2055</a> %H A129611 A. Karttunen, <a href="/A089840/a089840p.txt">Prolog-program which illustrates the construction of this and similar nonrecursive Catalan automorphisms.</a> %H A129611 <a href="/index/Per#IntegerPermutationCatAuto">Index entries for signature-permutations of Catalan automorphisms</a> %o A129611 (Constructive and destructive Scheme implementation of this automorphism. These act on S-expressions, i.e. list-structures:) %o A129611 (define (*A129611 s) (cond ((pair? s) (*A089859 (cons (car s) (*A089863 (cdr s))))) (else s))) %o A129611 (define (*A129611! s) (cond ((pair? s) (*A089863! (cdr s)) (*A089859! s))) s) %Y A129611 Inverse: A129612. %K A129611 nonn %O A129611 0,3 %A A129611 _Antti Karttunen_, May 22 2007