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 A089872 #6 Mar 31 2012 14:02:17 %S A089872 1,1,2,3,6,16,40,93,226,540,1336,3284,8068,19664,47880,116407,282866, %T A089872 687666,1673920,4077020,9929636 %N A089872 Number of cycles in range [A014137(n-1)..A014138(n-1)] of permutation A071665/A071666. %C A089872 The number of orbits to which the corresponding automorphism(s) partitions the set of A000108(n) binary trees with n internal nodes. %H A089872 A. Karttunen, <a href="/A089408/a089408.c.txt">C-program for computing the initial terms of this sequence</a> %K A089872 nonn %O A089872 0,3 %A A089872 _Antti Karttunen_, Nov 29 2003