A303630 - OEIS

A303630

Number of n X n 0..1 arrays with every element unequal to 2 or 3 horizontally or vertically adjacent elements, with upper left element zero.

0, 1, 0, 4, 20, 394, 7538, 501126, 43679228, 8515657512, 2784504147786

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,4

COMMENTS

Diagonal of A303636.

LINKS

EXAMPLE

Some solutions for n=5

..0..1..0..0..1. .0..1..0..0..1. .0..1..0..1..0. .0..1..0..1..0

..1..0..1..1..0. .1..0..1..1..0. .1..1..0..0..1. .1..0..0..1..1

..1..0..0..0..1. .0..0..1..1..0. .0..0..1..0..1. .0..1..1..0..0

..0..1..1..0..1. .1..1..0..0..1. .1..0..1..1..0. .1..0..0..1..1

..1..0..0..1..0. .0..1..0..1..0. .0..1..0..0..1. .0..1..0..1..0

CROSSREFS

KEYWORD

nonn

AUTHOR

R. H. Hardin, Apr 27 2018

STATUS

approved