login
This site is supported by donations to The OEIS Foundation.

 

Logo

The OEIS is looking to hire part-time people to help edit core sequences, upload scanned documents, process citations, fix broken links, etc. - Neil Sloane, njasloane@gmail.com

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A220165 Number of nonsquare simple imperfect squared rectangles of order n up to symmetry. 3
0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 9, 33, 104, 280, 948, 3014, 9494, 30302, 98897, 323372, 1080168, 3666666, 12604812 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,12

COMMENTS

A squared rectangle is a rectangle dissected into a finite number, two or more, of 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.

REFERENCES

See A002881 and A006983.

LINKS

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

Stuart E. Anderson, Simple Imperfect Squared Rectangles, orders 9 to 24

CROSSREFS

Cf. A002881, A006983, A002962, A002839.

Sequence in context: A048479 A031880 A231765 * A036543 A147269 A147123

Adjacent sequences:  A220162 A220163 A220164 * A220166 A220167 A220168

KEYWORD

nonn,hard

AUTHOR

Stuart E Anderson, Dec 06 2012

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent | More pages
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy .

Last modified May 28 10:34 EDT 2017. Contains 287240 sequences.