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%I #15 Jun 20 2018 11:12:54
%S 4,3,6,8,19,33,60,112,205,377,694,1276,2347,4317,7940,14604,26861,
%T 49405,90870,167136,307411,565417,1039964,1912792,3518173,6470929,
%U 11901894,21890996,40263819,74056709,136211524,250532052,460800285,847543861
%N Number of nX3 0..1 arrays with every element unequal to 0, 1, 2, 7 or 8 king-move adjacent elements, with upper left element zero.
%C Column 3 of A305586.
%H R. H. Hardin, <a href="/A305581/b305581.txt">Table of n, a(n) for n = 1..210</a>
%H Simon Plouffe <a href="http://vixra.org/abs/1409.0048">Conjectures of the OEIS, as of June 20, 2018.</a>
%F Empirical: a(n) = a(n-1) +a(n-2) +a(n-3) for n>5
%F Empirical: f(x)= -(2*x^4-5*x^3-x^2-x+4)*x/(x^3+x^2+x-1). - _Simon Plouffe_, Jun 20 2018
%e Some solutions for n=5
%e ..0..0..0. .0..1..1. .0..0..1. .0..0..0. .0..1..1. .0..0..1. .0..0..1
%e ..0..1..0. .1..0..1. .0..1..0. .0..0..0. .1..0..1. .0..1..0. .0..1..0
%e ..0..0..0. .1..1..1. .0..0..0. .0..0..0. .1..1..1. .0..0..0. .0..0..0
%e ..0..0..0. .1..0..1. .0..1..0. .0..1..0. .1..1..1. .0..1..0. .0..1..0
%e ..0..0..0. .1..1..1. .0..0..1. .0..0..0. .1..1..1. .1..0..0. .0..0..0
%Y Cf. A305586.
%K nonn
%O 1,1
%A _R. H. Hardin_, Jun 05 2018
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