A240121 Number of inequivalent ways to cut an n X n square into squares with integer sides, such that the dissection has two reflective symmetries in axes parallel to the sides, and no other reflective symmetries.

0, 0, 0, 1, 0, 13, 5, 183, 75, 4408, 1501, 180324

Offset

1,6

Comments

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

Links

Table of n, a(n) for n=1..12.

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

Example

This dissection is the only example for n=4:
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Crossrefs

Cf. A226979, A045846, A224239, A240120, A240122.

Sequence in context: A299959 A278445 A157799 * A081458 A296438 A010217

Adjacent sequences: A240118 A240119 A240120 * A240122 A240123 A240124

Keyword

nonn,more

Author

Ed Wynn, Apr 01 2014

Status

approved