A220166 Number of nonsquare simple squared rectangles of order n up to symmetry.

0, 0, 0, 0, 0, 0, 0, 0, 3, 6, 22, 76, 246, 848, 2889, 9964, 34440, 119875, 420525, 1482802, 5254679, 18713933, 66968081, 240735712

Offset

1,9

Comments

A squared rectangle (which may be a square) is a rectangle dissected into a finite number, two or more, of integer sized squares. If no two of these squares have the same size the squared rectangle is perfect. A squared rectangle is simple if it does not contain a smaller squared rectangle. The order of a squared rectangle is the number of constituent squares. This sequence counts nonsquare simple perfect squared rectangles and nonsquare simple imperfect squared rectangles.

References

See A006983 and A217156 for further links.

Links

Table of n, a(n) for n=1..24.

S. E. Anderson, Simple Perfect Squared Rectangles [Nonsquare rectangles only]

S. E. Anderson, Simple Imperfect Squared Rectangles [Nonsquare rectangles only]

Crossrefs

Cf. A219766, A220165, A002839, A002881.

Sequence in context: A208939 A209067 A389295 * A220167 A378731 A243336

Adjacent sequences: A220163 A220164 A220165 * A220167 A220168 A220169

Keyword

nonn,hard

Author

Stuart E Anderson, Dec 06 2012

Extensions

a(9)-a(24) from Stuart E Anderson Dec 07 2012

Status

approved