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

%I #7 Feb 20 2019 12:24:43

%S 7,27,99,413,1601,6349,25153,99287,392907,1553391,6142251,24289277,

%T 96042921,379779797,1501741049,5938235583,23481235283,92850420759,

%U 367152906387,1451810964181,5740809545409,22700542022605,89763402870129

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

%H R. H. Hardin, <a href="/A282642/b282642.txt">Table of n, a(n) for n = 1..210</a>

%F 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).

%F 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

%e Some solutions for n=4:

%e ..0..1..0. .0..0..0. .0..0..1. .1..0..0. .0..0..0. .0..1..1. .0..0..0

%e ..0..0..0. .1..0..0. .1..0..1. .0..1..0. .1..1..0. .0..0..0. .0..1..0

%e ..0..0..0. .0..0..0. .0..0..0. .0..0..0. .0..0..0. .1..0..0. .0..1..0

%e ..0..1..1. .0..0..0. .0..0..1. .1..0..1. .0..1..0. .0..0..0. .0..0..0

%Y Column 3 of A282647.

%K nonn

%O 1,1

%A _R. H. Hardin_, Feb 20 2017