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 A086427 #8 Oct 15 2015 10:55:24 %S A086427 0,1,3,2,8,6,7,5,4,22,19,20,15,14,21,16,18,13,12,17,10,11,9,64,60,61, %T A086427 52,51,62,53,55,41,40,54,38,39,37,63,56,57,43,42,59,47,50,36,34,49,35, %U A086427 32,31,58,44,46,27,26,48,29,33,30,45,24,25,28,23,196,191,192,178,177 %N A086427 Permutation of natural numbers induced by the Catalan bijection gma086427 acting on symbolless S-expressions encoded by A014486/A063171. %C A086427 This Catalan bijection rotates by "half step" the interpretations (pp)-(rr) of Stanley, using the "descending slope" mapping illustrated in A086431. %H A086427 A. Karttunen, <a href="http://www.iki.fi/~kartturi/matikka/Nekomorphisms/gatomorf.htm">Gatomorphisms</a> (With the complete Scheme source) %H A086427 <a href="/index/Per#IntegerPermutationCatAuto">Index entries for signature-permutations induced by Catalan automorphisms</a> %Y A086427 Inverse: A086428. a(n) = A086431(A086428(A086431(n))) = A057164(A085173(A057164(n))) = A086425(A057501(A086426(n))). Occurs in A073200. Cf. also A086429 (whole step rotate). %Y A086427 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 A086427 nonn %O A086427 0,3 %A A086427 _Antti Karttunen_, Jun 23 2003