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 A086428 #8 Oct 15 2015 10:55:24 %S A086428 0,1,3,2,8,7,5,6,4,22,20,21,18,17,13,12,15,19,16,10,11,14,9,64,61,62, %T A086428 55,54,63,57,59,50,49,58,46,48,45,36,34,35,32,31,41,40,52,60,53,43,56, %U A086428 47,44,27,26,29,33,30,38,39,51,42,24,25,28,37,23,196,192,193,181,180 %N A086428 Permutation of natural numbers induced by the Catalan bijection gma086428 acting on symbolless S-expressions encoded by A014486/A063171. %C A086428 This Catalan bijection rotates by "half step" the interpretations (pp)-(rr) of Stanley, using the "descending slope" mapping illustrated in A086431. %H A086428 A. Karttunen, <a href="http://www.iki.fi/~kartturi/matikka/Nekomorphisms/gatomorf.htm">Gatomorphisms</a> (With the complete Scheme source) %H A086428 <a href="/index/Per#IntegerPermutationCatAuto">Index entries for signature-permutations induced by Catalan automorphisms</a> %Y A086428 Inverse: A086427. a(n) = A086431(A086427(A086431(n))) = A057164(A085174(A057164(n))) = A086425(A057502(A086426(n))). Occurs in A073200. Cf. also A086430 (whole step rotate). %Y A086428 Number of cycles: A002995. Number of fixed points: A019590. Max. cycle size: A057543. (In range [A014137(n-1)..A014138(n-1)] of this permutation, possibly shifted one term left or right). %K A086428 nonn %O A086428 0,3 %A A086428 _Antti Karttunen_, Jun 23 2003