A306123 Number of nXn 0..1 arrays with every element unequal to 0, 1, 3, 4, 6 or 7 king-move adjacent elements, with upper left element zero.

1, 5, 9, 70, 517, 4872, 143839, 8721531, 902758342, 197546692104

Offset

1,2

Comments

Diagonal of A306129.

Links

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

Example

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

Crossrefs

Cf. A306129.

Sequence in context: A179100 A358966 A304538 * A365580 A192202 A249937

Adjacent sequences: A306120 A306121 A306122 * A306124 A306125 A306126

Keyword

nonn

Author

R. H. Hardin, Jun 22 2018

Status

approved