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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.

A240122 Number of inequivalent ways to cut an n X n square into squares with integer sides, such that the dissection has 90-degree rotational symmetry and no reflective symmetry.

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%I A240122 #13 Jul 23 2025 11:01:12
%S A240122 0,0,0,0,1,2,12,40,154,760,3260,22730
%N A240122 Number of inequivalent ways to cut an n X n square into squares with integer sides, such that the dissection has 90-degree rotational symmetry and no reflective symmetry.
%H A240122 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 A240122 The two dissections for n=6:
%e A240122 -------------    -------------
%e A240122 | |   | | | |    | |   | | | |
%e A240122 ---   -------    ---   -------
%e A240122 | |   | |   |    | |   | |   |
%e A240122 ---------   |    ---------   |
%e A240122 | | |   |   |    | | | | |   |
%e A240122 -----   -----    -------------
%e A240122 |   |   | | |    |   | | | | |
%e A240122 |   ---------        ---------
%e A240122 |   | |   | |    |   | |   | |
%e A240122 -------   ---    -------   ---
%e A240122 | | | |   | |    | | | |   | |
%e A240122 -------------    -------------
%Y A240122 Cf. A226979, A045846, A224239, A240120, A240121.
%K A240122 nonn,more
%O A240122 1,6
%A A240122 _Ed Wynn_, Apr 01 2014