A304420 Number of n X n 0..1 arrays with every element unequal to 1, 2, 3, 4 or 5 king-move adjacent elements, with upper left element zero.

0, 7, 124, 9304, 1712347, 898146670, 1305482386171, 5296781617645719, 59891404546831242351

Offset

1,2

Comments

Diagonal of A304427.

Links

Table of n, a(n) for n=1..9.

Example

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

Crossrefs

Cf. A304427.

Sequence in context: A192566 A322090 A360337 * A217910 A316276 A220615

Adjacent sequences: A304417 A304418 A304419 * A304421 A304422 A304423

Keyword

nonn

Author

R. H. Hardin, May 12 2018

Status

approved