A303519 Number of n X n 0..1 arrays with every element equal to 0, 1, 3, 4, 5 or 6 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.

1, 3, 18, 103, 1758, 102779, 15768709, 6835357512, 8858057538977

Offset

1,2

Comments

Diagonal of A303525.

Links

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

Example

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

Crossrefs

Cf. A303525.

Sequence in context: A038158 A327828 A009021 * A124408 A136779 A106328

Adjacent sequences: A303516 A303517 A303518 * A303520 A303521 A303522

Keyword

nonn

Author

R. H. Hardin, Apr 25 2018

Status

approved