A300459 Number of n X n 0..1 arrays with every element equal to 2, 3 or 4 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.

0, 1, 2, 28, 1146, 78195, 17675111, 9829599051, 14061129641181, 51771244646074395

Offset

1,3

Comments

Diagonal of A300465.

Links

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

Example

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

Crossrefs

Cf. A300465.

Sequence in context: A292806 A113633 A186491 * A009674 A143598 A324077

Adjacent sequences: A300456 A300457 A300458 * A300460 A300461 A300462

Keyword

nonn

Author

R. H. Hardin, Mar 06 2018

Status

approved