A318017 Number of nXn 0..1 arrays with every element unequal to 0, 1, 2 or 4 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.

1, 6, 45, 569, 12039, 400016, 20241433, 1699138124, 223853493247, 46952248817665

Offset

1,2

Comments

Diagonal of A318024.

Links

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

Example

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

Crossrefs

Cf. A318024.

Sequence in context: A245493 A078865 A160492 * A356487 A322089 A273091

Adjacent sequences: A318014 A318015 A318016 * A318018 A318019 A318020

Keyword

nonn

Author

R. H. Hardin, Aug 12 2018

Status

approved