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 A219993 #4 Dec 02 2012 18:44:31 %S A219993 1,1,1255,99621,25445515,3830482893,735394314429,125449223494157, %T A219993 22714686725936048,3988620629294917699,711716770252031164458, %U A219993 125923932676484373629595,22380459664033815935121317,3968099315998651724194784995,704461390023584621534680605823 %N A219993 Number of tilings of a 10 X n rectangle using dominoes and right trominoes. %H A219993 Alois P. Heinz, <a href="/A219993/b219993.txt">Table of n, a(n) for n = 0..150</a> %Y A219993 Column k=10 of A219987. %K A219993 nonn %O A219993 0,3 %A A219993 _Alois P. Heinz_, Dec 02 2012