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 A089871 #5 Mar 31 2012 14:02:17 %S A089871 1,1,2,2,2,10,40,240,5040,388080,5045040,94643905622666400 %N A089871 Least common multiple of all cycle sizes in range [A014137(n-1)..A014138(n-1)] of permutation A071663/A071664. %H A089871 A. Karttunen, <a href="/A089408/a089408.c.txt">C-program for computing the initial terms of this sequence</a> %Y A089871 Cf. A089403. %K A089871 nonn %O A089871 0,3 %A A089871 _Antti Karttunen_, Nov 29 2003