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 A072407 #8 Nov 30 2015 09:39:20 %S A072407 0,1,0,0,0,0,0,2,1,1,0,7,5,16,14,40,41,120,131,321,402,901,1210,2590, %T A072407 3621,7371,10841,21178,32222,61273,95408,177384,282405,515174,833295, %U A072407 1500030,2455337,4372535,7229231,12761691,21260746,37286778,62483221,109014426,183542099,318906720,538889399,933361886,1581666042 %N A072407 Canonically 2-indecomposable posets with n antichains. %H A072407 M. Erné, J. Heitzig and J. Reinhold, <a href="http://www.combinatorics.org/ojs/index.php/eljc/article/view/v9i1r24">On the number of distributive lattices</a>, Electronic Journal of Combinatorics, 9 (2002), #R24. %Y A072407 Cf. A006982, A072361. %K A072407 nonn %O A072407 1,8 %A A072407 _N. J. A. Sloane_, Aug 01 2002