A318221 Number of nX7 0..1 arrays with every element unequal to 2, 3, 4 or 5 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.

0, 45, 1975, 123415, 6735734, 381426500, 21578384304, 1220340668071, 69013808316210, 3902978619371586, 220727316564416823, 12482916861238637731, 705953461210591911518, 39924185063402562186842, 2257854998649283317636359

Offset

1,2

Comments

Column 7 of A318222.

Links

R. H. Hardin, Table of n, a(n) for n = 1..210

Example

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

Crossrefs

Cf. A318222.

Sequence in context: A143170 A328351 A203828 * A162885 A163231 A163749

Adjacent sequences: A318218 A318219 A318220 * A318222 A318223 A318224

Keyword

nonn

Author

R. H. Hardin, Aug 21 2018

Status

approved