A316804 Number of nX4 0..1 arrays with every element unequal to 0, 1, 2, 3, 4, 5 or 6 king-move adjacent elements, with upper left element zero.

8, 128, 1905, 28248, 420345, 6256258, 93109949, 1385723098, 20623265507, 306929355068, 4567929663745, 67983009966484, 1011769004146827, 15057828687751316, 224100761989675875, 3335218680314293250

Offset

1,1

Comments

Column 4 of A316808.

Links

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

Formula

Empirical: a(n) = 15*a(n-1) -5*a(n-2) +50*a(n-3) -18*a(n-4) -81*a(n-5) +4*a(n-6) +20*a(n-7)

Example

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

Crossrefs

Cf. A316808.

Sequence in context: A302011 A301780 A348804 * A317521 A299650 A300204

Adjacent sequences: A316801 A316802 A316803 * A316805 A316806 A316807

Keyword

nonn

Author

R. H. Hardin, Jul 14 2018

Status

approved