A317734 Number of nXn 0..1 arrays with every element unequal to 2 or 3 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.

0, 1, 1, 4, 14, 22, 274, 676, 3242, 11126, 82244, 533332, 3119164, 25366420, 294184154, 2840519658, 33041657228, 516226778736, 8641833554020

Offset

1,4

Comments

Diagonal of A317741.

Links

Table of n, a(n) for n=1..19.

Example

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

Crossrefs

Cf. A317741.

Sequence in context: A279414 A199987 A201016 * A154046 A000054 A063616

Adjacent sequences: A317731 A317732 A317733 * A317735 A317736 A317737

Keyword

nonn

Author

R. H. Hardin, Aug 05 2018

Status

approved