A305041 Number of n X n 0..1 arrays with every element unequal to 0, 2, 3, 6 or 7 king-move adjacent elements, with upper left element zero.

1, 4, 5, 11, 55, 137, 116, 273937, 2062731, 1797964, 125122422419, 5525083659668

Offset

1,2

Comments

Diagonal of A305047.

Links

Table of n, a(n) for n=1..12.

Example

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

Crossrefs

Cf. A305047.

Sequence in context: A304135 A251240 A361529 * A316731 A253086 A260624

Adjacent sequences: A305038 A305039 A305040 * A305042 A305043 A305044

Keyword

nonn

Author

R. H. Hardin, May 24 2018

Status

approved