A316687 Number of nXn 0..1 arrays with every element unequal to 0, 1, 2, 6, 7 or 8 king-move adjacent elements, with upper left element zero.

1, 4, 8, 23, 88, 2081, 61454, 2431114, 257262996, 52155197669, 17033276992389, 11335703888987492, 14840834772251861064, 35171617032782262638585

Offset

1,2

Comments

Diagonal of A316693.

Links

Table of n, a(n) for n=1..14.

Example

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

Crossrefs

Cf. A316693.

Sequence in context: A026596 A181688 A243557 * A083504 A277291 A362212

Adjacent sequences: A316684 A316685 A316686 * A316688 A316689 A316690

Keyword

nonn

Author

R. H. Hardin, Jul 10 2018

Status

approved