0,2

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).

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

Wikipedia, Takuzu

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 ]

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

nonn,more

Brian Kell, Dec 30 2014

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

approved