A304466 Number of n X n 0..1 arrays with every element unequal to 0, 1, 2, 3 or 6 king-move adjacent elements, with upper left element zero.

1, 8, 41, 322, 5063, 89071, 1802240, 101407827, 8813328376, 823379005870

Offset

1,2

Comments

Diagonal of A304472.

Links

Table of n, a(n) for n=1..10.

Example

Some solutions for n=5
..0..0..0..0..0. .0..1..1..1..1. .0..0..1..1..0. .0..1..1..1..1
..0..0..0..0..0. .0..1..1..1..1. .0..1..1..0..0. .0..0..1..1..1
..0..0..0..1..0. .0..1..1..1..1. .1..1..1..1..1. .1..1..1..1..1
..0..0..0..1..1. .0..1..1..1..1. .1..1..0..1..1. .1..1..1..0..0
..1..0..0..0..0. .0..1..1..1..0. .0..1..0..0..1. .1..1..1..1..0

Crossrefs

Cf. A304472.

Sequence in context: A188209 A026953 A280068 * A228480 A067301 A295936

Adjacent sequences: A304463 A304464 A304465 * A304467 A304468 A304469

Keyword

nonn

Author

R. H. Hardin, May 13 2018

Status

approved