A317856 Number of nXn 0..1 arrays with every element unequal to 1, 2 or 4 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.

0, 3, 4, 56, 350, 3315, 33238, 517734, 8875636, 219127394, 6925306920

Offset

1,2

Comments

Diagonal of A317863.

Links

Table of n, a(n) for n=1..11.

Example

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

Crossrefs

Cf. A317863.

Sequence in context: A272337 A132678 A166850 * A331725 A067093 A041105

Adjacent sequences: A317853 A317854 A317855 * A317857 A317858 A317859

Keyword

nonn

Author

R. H. Hardin, Aug 09 2018

Status

approved