A317816 Number of nXn 0..1 arrays with every element unequal to 1, 2 or 3 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.

0, 5, 35, 702, 8556, 296968, 7370716, 384248160, 21424520640, 1842317433367, 222676829507057, 36099873530494859, 9133843424563202164

Offset

1,2

Comments

Diagonal of A317823.

Links

Table of n, a(n) for n=1..13.

Example

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

Crossrefs

Cf. A317823.

Sequence in context: A089043 A317995 A260075 * A034236 A058015 A053420

Adjacent sequences: A317813 A317814 A317815 * A317817 A317818 A317819

Keyword

nonn

Author

R. H. Hardin, Aug 07 2018

Status

approved