A303405 Number of n X n 0..1 arrays with every element equal to 1, 2, 4, 5 or 6 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.

0, 3, 28, 168, 4013, 236326, 24386918, 4298730424, 1222253462556

Offset

1,2

Comments

Diagonal of A303410.

Links

Table of n, a(n) for n=1..9.

Example

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

Crossrefs

Cf. A303410.

Sequence in context: A012762 A012778 A302522 * A074922 A285365 A366689

Adjacent sequences: A303402 A303403 A303404 * A303406 A303407 A303408

Keyword

nonn

Author

R. H. Hardin, Apr 23 2018

Status

approved