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 A089423 #6 Mar 31 2012 14:02:17 %S A089423 1,1,2,6,12,120,120,840,840,5040,5040,55440,55440,720720,720720, %T A089423 720720,720720,24504480,24504480,465585120,465585120 %N A089423 Least common multiple of all cycle sizes in range [A014137(n-1)..A014138(n-1)] of permutation A082335/A082336 (and also of A082349/A082350, to be proved). %H A089423 A. Karttunen, <a href="/A089408/a089408.c.txt">C-program for computing the initial terms of this sequence</a> %Y A089423 Bisection: A089431. %K A089423 nonn %O A089423 0,3 %A A089423 _Antti Karttunen_, Nov 29 2003