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 A240124 #12 Apr 05 2014 22:25:39 %S A240124 0,0,0,0,2,19,109,1781,13660,397689,5368943,289864745 %N A240124 Number of inequivalent ways to cut an n X n square into squares with integer sides, such that the dissection has 180-degree rotational symmetry, but no other symmetries. %H A240124 Ed Wynn, <a href="http://arxiv.org/abs/1308.5420">Exhaustive generation of Mrs Perkins's quilt square dissections for low orders</a>, arXiv:1308.5420 %e A240124 The two dissections for n=5: %e A240124 ----------- ----------- %e A240124 | | | | | | | | | %e A240124 | | --- --- ----- %e A240124 | | | | | | | | | %e A240124 ----------- ----------- %e A240124 | | | | | | | | | | | | %e A240124 ----------- ----------- %e A240124 | | | | | | | | | %e A240124 --- | | ----- --- %e A240124 | | | | | | | | | %e A240124 ----------- ----------- %Y A240124 Cf. A226980, A045846, A224239, A240123, A240125. %K A240124 nonn,more %O A240124 1,5 %A A240124 _Ed Wynn_, Apr 01 2014