login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A253316 Number of 2n X 2n Takuzu grids. 1
1, 2, 72, 4140, 4111116, 48183195384 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

A Takuzu grid is a 2n X 2n zero-one matrix with the following properties:

1. Every row and every column has n zeros and n ones.

2. No row or column has three consecutive zeros or three consecutive ones.

3. All rows are distinct, and all columns are distinct (but a row may be the same as a column).

LINKS

Table of n, a(n) for n=0..5.

Wikipedia, Takuzu

EXAMPLE

The following is a 4 X 4 Takuzu grid:

[ 0  1  1  0 ]

[ 1  0  0  1 ]

[ 0  0  1  1 ]

[ 1  1  0  0 ]

CROSSREFS

Cf. A058527.

Number of possible rows equals A003440.

Sequence in context: A221549 A289197 A174582 * A051443 A246486 A123072

Adjacent sequences:  A253313 A253314 A253315 * A253317 A253318 A253319

KEYWORD

nonn,more

AUTHOR

Brian Kell, Dec 30 2014

EXTENSIONS

a(5) from Frans J. Faase, Dec 14 2015

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 March 30 19:28 EDT 2020. Contains 333127 sequences. (Running on oeis4.)