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 A192097 #18 Dec 16 2016 03:05:48 %S A192097 1,1,2,4,8,8,16,28,40,80,144,252,456,840 %N A192097 Number of tatami tilings of an n X n square region with n monomers and floor(n * (n - 1) / 4) horizontal dimers. %C A192097 A tatami tiling consists of dimers (1 X 2) and monomers (1 X 1) where no four meet at a point. %C A192097 There are at most n * (n - 1) / 2 horizontal dimers in any tiling of an n X n square with n monomers. %C A192097 If there are floor(n * (n - 1) / 4) horizontal dimers, the numbers of horizontal dimers and vertical dimers differ by at most one. %H A192097 A. Erickson, F. Ruskey, M. Schurch and J. Woodcock, <a href="http://www.combinatorics.org/Volume_18/Abstracts/v18i1p109.html">Monomer-Dimer Tatami Tilings of Rectangular Regions</a>, Electronic Journal of Combinatorics, 18(1) (2011) P109, 24 pages. %Y A192097 Cf. A192095. %K A192097 nonn,more %O A192097 0,3 %A A192097 _Frank Ruskey_ and Yuji Yamauchi (eugene.uti(AT)gmail.com), Jul 15 2011