A240120 Number of inequivalent ways to cut an n X n square into squares with integer sides, such that the dissection has reflective symmetry in both diagonals and no other reflective symmetries.

0, 0, 0, 1, 1, 9, 19, 121, 275, 2489, 7217, 86775

Offset: 1

Author

Ed Wynn, Apr 01 2014

Keywords

• nonn
• more

Comments

'Inequivalent' has the same sense as in A224239: we do not regard dissections that differ by a rotation and/or reflection as distinct.

The two reflective symmetries imply 180-degree (but not 90-degree) rotational symmetry.

Examples

			This is the single dissection for n=4:
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|   | | |
|   -----
|   | | |
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| | |   |
-----   |
| | |   |
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Links

• Ed Wynn, Exhaustive generation of Mrs Perkins's quilt square dissections for low orders, arXiv:1308.5420

Crossrefs

Cf. A226979, A045846, A224239, A240121, A240122.