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 A220166 #9 Dec 07 2012 20:29:35 %S A220166 0,0,0,0,0,0,0,0,3,6,22,76,246,848,2889,9964,34440,119875,420525, %T A220166 1482802,5254679,18713933,66968081,240735712 %N A220166 Number of nonsquare simple squared rectangles of order n up to symmetry. %C A220166 A squared rectangle (which may be a square) is a rectangle dissected into a finite number, two or more, of integer sized squares. If no two of these squares have the same size the squared rectangle is perfect. A squared rectangle is simple if it does not contain a smaller squared rectangle. The order of a squared rectangle is the number of constituent squares. This sequence counts nonsquare simple perfect squared rectangles and nonsquare simple imperfect squared rectangles. %D A220166 See A006983 and A217156 for further links. %H A220166 S. E. Anderson, <a href="http://www.squaring.net/sq/sr/spsr/spsr.html">Simple Perfect Squared Rectangles</a> [Nonsquare rectangles only] %H A220166 S. E. Anderson, <a href="http://www.squaring.net/sq/sr/sisr/sisr.html">Simple Imperfect Squared Rectangles</a> [Nonsquare rectangles only] %Y A220166 Cf. A219766, A220165, A002839, A002881. %K A220166 nonn,hard %O A220166 1,9 %A A220166 _Stuart E Anderson_, Dec 06 2012 %E A220166 a(9)-a(24) from _Stuart E Anderson_ Dec 07 2012