A301602 Number of n X n 0..1 arrays with every element equal to 0, 2 or 3 horizontally or vertically adjacent elements, with upper left element zero.

1, 2, 2, 25, 330, 8888, 591585, 83224304, 23865691820, 14092825824108

Offset

1,2

Comments

Diagonal of A301608.

Links

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

Example

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

Crossrefs

Cf. A301608.

Sequence in context: A032084 A306062 A195967 * A354898 A120979 A348587

Adjacent sequences: A301599 A301600 A301601 * A301603 A301604 A301605

Keyword

nonn

Author

R. H. Hardin, Mar 24 2018

Status

approved