A282642 - OEIS

A282642

Number of n X 3 0..1 arrays with no 1 equal to more than one of its king-move neighbors.

7, 27, 99, 413, 1601, 6349, 25153, 99287, 392907, 1553391, 6142251, 24289277, 96042921, 379779797, 1501741049, 5938235583, 23481235283, 92850420759, 367152906387, 1451810964181, 5740809545409, 22700542022605, 89763402870129

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OFFSET

1,1

LINKS

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

FORMULA

Empirical: a(n) = 2*a(n-1) + 6*a(n-2) + 8*a(n-3) - 5*a(n-4) + 2*a(n-5) - 2*a(n-6).

Empirical g.f.: x*(7 + 13*x + 3*x^2 - 3*x^3 - 2*x^5) / (1 - 2*x - 6*x^2 - 8*x^3 + 5*x^4 - 2*x^5 + 2*x^6). - Colin Barker, Feb 20 2019

EXAMPLE

Some solutions for n=4:

..0..1..0. .0..0..0. .0..0..1. .1..0..0. .0..0..0. .0..1..1. .0..0..0

..0..0..0. .1..0..0. .1..0..1. .0..1..0. .1..1..0. .0..0..0. .0..1..0

..0..0..0. .0..0..0. .0..0..0. .0..0..0. .0..0..0. .1..0..0. .0..1..0

..0..1..1. .0..0..0. .0..0..1. .1..0..1. .0..1..0. .0..0..0. .0..0..0

CROSSREFS

Column 3 of A282647.

Sequence in context: A135914 A213588 A305653 * A185080 A006350 A054485

Adjacent sequences: A282639 A282640 A282641 * A282643 A282644 A282645

KEYWORD

nonn

AUTHOR

R. H. Hardin, Feb 20 2017

STATUS

approved