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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.
3

%I #12 Apr 05 2014 22:25:39

%S 0,0,0,0,2,19,109,1781,13660,397689,5368943,289864745

%N 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 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 The two dissections for n=5:

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%Y Cf. A226980, A045846, A224239, A240123, A240125.

%K nonn,more

%O 1,5

%A _Ed Wynn_, Apr 01 2014