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 A121195 #12 Oct 19 2017 03:15:03 %S A121195 1,12,152,2538,45084,851717 %N A121195 Consider the tiling of the plane with squares of two different sizes as in Fig. 2.4.2(g) of Grünbaum and Shephard, p. 74. a(n) is the number of connected figures that can be formed on this tiling, from n big squares and n small squares. %C A121195 The Zucca web site calls these figures "n-BiSquares". %D A121195 Branko Grünbaum and G. C. Shephard, Tilings and Patterns. W. H. Freeman, New York, 1987. %H A121195 Livio Zucca, <a href="http://www.iread.it/lz/polymultiforms2.html">PolyMultiForms</a> %H A121195 Livio Zucca, <a href="/A121195/a121195.gif">The 12 2-BiSquares</a> (from the Zucca web site). %Y A121195 Cf. A121196, A121197, A121198. %K A121195 nonn,more %O A121195 1,2 %A A121195 _N. J. A. Sloane_, Aug 17 2006 %E A121195 More terms from _Don Reble_, Aug 17 2007