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%I #4 Apr 28 2018 09:29:50
%S 0,3,5,18,61,209,702,2381,8069,27330,92581,313641,1062502,3599373,
%T 12193421,41307034,139933701,474046225,1605902110,5440232205,
%U 18429595637,62432996082,211501059173,716491292025,2427220807318,8222571457613
%N Number of nX2 0..1 arrays with every element unequal to 2, 3 or 4 king-move adjacent elements, with upper left element zero.
%C Column 2 of A303690.
%H R. H. Hardin, <a href="/A303684/b303684.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 3*a(n-1) +a(n-2) +2*a(n-3) -2*a(n-4) -4*a(n-5) for n>6
%e Some solutions for n=5
%e ..0..1. .0..0. .0..0. .0..1. .0..1. .0..1. .0..0. .0..1. .0..1. .0..1
%e ..0..1. .1..1. .1..1. .0..1. .1..0. .1..0. .1..1. .0..1. .1..0. .0..1
%e ..0..0. .0..0. .1..0. .0..0. .0..1. .0..0. .0..1. .0..0. .1..0. .1..0
%e ..1..0. .0..0. .0..0. .1..0. .0..1. .0..1. .0..1. .0..1. .1..1. .0..1
%e ..0..1. .1..1. .1..1. .1..0. .0..1. .1..0. .1..0. .0..1. .0..0. .0..1
%Y Cf. A303690.
%K nonn
%O 1,2
%A _R. H. Hardin_, Apr 28 2018
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