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 A075224 #12 Dec 05 2014 02:59:53 %S A075224 0,0,0,0,0,0,0,0,6,25,53,47,97,281,280,343,345,1367,619,2478,1504, %T A075224 8292,1811,16742,3458,48453,5459,95311,9416,333739 %N A075224 Number of anisohedral polyiamonds with n cells. %C A075224 A tiling is isohedral if the symmetries of the tiling act transitively on the tiles; a shape is anisohedral if it tiles the plane, but not isohedrally. %D A075224 Branko Grünbaum and G. C. Shephard, Tilings and Patterns. W. H. Freeman, New York, 1987, Section 9.4. %H A075224 Joseph Myers, <a href="http://www.polyomino.org.uk/mathematics/polyform-tiling/">Polyiamond tiling</a> %Y A075224 Cf. A071332, A075216, A075217, A075218, A075219, A075220, A075221, A075222, A075223, A075206, A075215. %K A075224 hard,nonn %O A075224 1,9 %A A075224 _Joseph Myers_, Sep 08 2002 %E A075224 More terms from _Joseph Myers_, Nov 11 2003 %E A075224 a(29) and a(30) from _Joseph Myers_, Nov 21 2010