A304598 Number of n X n 0..1 arrays with every element unequal to 0, 1, 2, 5 or 6 king-move adjacent elements, with upper left element zero.

1, 4, 13, 73, 560, 6007, 75463, 1874284, 62934491, 2085910493, 94776909801, 7409071360844, 887762245576310

Offset

1,2

Comments

Diagonal of A304604.

Links

Table of n, a(n) for n=1..13.

Example

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

Crossrefs

Cf. A304604.

Sequence in context: A374825 A121452 A249165 * A171756 A235385 A144055

Adjacent sequences: A304595 A304596 A304597 * A304599 A304600 A304601

Keyword

nonn

Author

R. H. Hardin, May 15 2018

Status

approved