A316642 Number of nXn 0..1 arrays with every element unequal to 1, 2, 4, 5, 7 or 8 king-move adjacent elements, with upper left element zero.

0, 3, 15, 42, 3988, 43604, 1396674, 331807728, 22368384180, 4961341851222

Offset

1,2

Comments

Diagonal of A316648.

Links

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

Example

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

Crossrefs

Cf. A316648.

Sequence in context: A366576 A093627 A192060 * A146805 A147057 A330322

Adjacent sequences: A316639 A316640 A316641 * A316643 A316644 A316645

Keyword

nonn

Author

R. H. Hardin, Jul 09 2018

Status

approved