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%I #4 May 16 2018 14:31:31
%S 3,9,13,30,66,123,252,535,1074,2194,4530,9231,18873,38722,79180,
%T 161992,331766,678927,1389398,2844206,5821252,11914196,24386446,
%U 49913147,102159115,209097391,427973147,875956927,1792880557,3669604702
%N Number of nX3 0..1 arrays with every element unequal to 0, 1, 3, 5 or 6 king-move adjacent elements, with upper left element zero.
%C Column 3 of A304669.
%H R. H. Hardin, <a href="/A304664/b304664.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = a(n-1) +4*a(n-3) +2*a(n-5) -a(n-7) -2*a(n-9) -2*a(n-11) -a(n-12)
%e Some solutions for n=5
%e ..0..1..1. .0..0..0. .0..0..0. .0..0..0. .0..0..1. .0..1..0. .0..0..0
%e ..0..0..1. .1..0..0. .0..0..1. .0..0..1. .0..1..1. .0..0..0. .0..0..0
%e ..0..0..0. .0..0..0. .0..0..0. .0..1..1. .1..1..1. .0..0..0. .0..0..1
%e ..0..0..0. .0..0..0. .0..0..0. .0..0..0. .1..1..1. .0..0..0. .0..1..1
%e ..1..0..0. .0..0..0. .0..1..0. .0..0..1. .1..1..1. .1..0..0. .1..1..1
%Y Cf. A304669.
%K nonn
%O 1,1
%A _R. H. Hardin_, May 16 2018