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%I #7 Feb 21 2018 14:29:32
%S 1,5,12,37,104,301,864,2485,7144,20541,59056,169797,488184,1403597,
%T 4035520,11602645,33359112,95911773,275758800,792842341,2279524632,
%U 6553929197,18843397088,54177212405,155766517544,447848955517
%N Number of n X 2 0..1 arrays with every element equal to 0, 2, 3 or 4 king-move adjacent elements, with upper left element zero.
%C Column 2 of A297915.
%H R. H. Hardin, <a href="/A297909/b297909.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 5*a(n-2) + 8*a(n-3) + 4*a(n-4).
%F Empirical g.f.: x*(1 + 5*x + 7*x^2 + 4*x^3) / ((1 + x)*(1 - x - 4*x^2 - 4*x^3)). - _Colin Barker_, Feb 21 2018
%e Some solutions for n=7:
%e ..0..1. .0..1. .0..1. .0..0. .0..0. .0..1. .0..1. .0..1. .0..1. .0..0
%e ..1..1. .1..1. .1..1. .1..0. .1..0. .0..0. .1..1. .1..1. .1..1. .0..1
%e ..1..0. .0..0. .1..0. .1..1. .1..1. .0..1. .1..1. .1..1. .0..0. .0..0
%e ..0..0. .0..1. .1..1. .1..1. .0..1. .0..0. .0..1. .0..0. .1..0. .1..0
%e ..0..1. .1..1. .0..0. .1..0. .0..0. .0..1. .1..1. .0..0. .0..0. .1..1
%e ..1..1. .1..0. .1..0. .1..1. .0..1. .1..1. .1..0. .1..0. .1..1. .0..0
%e ..1..1. .0..0. .1..1. .0..1. .1..1. .1..1. .0..0. .1..1. .1..1. .0..1
%Y Cf. A297915.
%K nonn
%O 1,2
%A _R. H. Hardin_, Jan 08 2018
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