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

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A226981 Number of ways to cut an n X n square into squares with integer sides, reduced for symmetry, where the orbits under the symmetry group of the square, D4, have 8 elements. 5
0, 0, 0, 1, 45, 1194, 55777, 4471175, 669049507, 187616301623, 98793450008033, 97702667035688951 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,5

LINKS

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

Christopher Hunt Gribble, C++ program for A226978, A226979, A226980, A226981, A227004

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

FORMULA

A226978(n) + A226979(n) + A226980(n) + A226981(n) = A224239(n).

1*A226978(n) + 2*A226979(n) + 4*A226980(n) + 8*A226981(n) = A045846(n).

EXAMPLE

For n=5, there are 45 dissections where the orbits under the symmetry group of the square, D4, have 8 elements.

For n=4, this is the only dissection:

---------

|   | | |

|   -----

|   |   |

-----   |

| | |   |

---------

| | | | |

---------

CROSSREFS

Cf. A045846, A034295, A219924, A224239, A226978, A226979, A226980.

Sequence in context: A320822 A229796 A143400 * A173000 A004350 A199518

Adjacent sequences:  A226978 A226979 A226980 * A226982 A226983 A226984

KEYWORD

nonn,more

AUTHOR

Christopher Hunt Gribble, Jun 25 2013

EXTENSIONS

a(8)-a(12) from Ed Wynn, Apr 02 2014

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
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified April 19 01:29 EDT 2019. Contains 322237 sequences. (Running on oeis4.)