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%I #9 Mar 22 2018 09:47:29
%S 1,2,3,4,8,17,31,71,166,365,856,2020,4675,10985,25869,60578,142347,
%T 334748,785984,1846905,4340975,10198815,23965446,56319245,132336896,
%U 310971516,730753851,1717154937,4035069173,9481906914,22281135563
%N Number of n X 2 0..1 arrays with each 1 adjacent to 3 or 4 king-move neighboring 1s.
%C Column 2 of A296115.
%H R. H. Hardin, <a href="/A296109/b296109.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = a(n-1) + 2*a(n-2) + 5*a(n-3) - 2*a(n-4) - 6*a(n-5) - 4*a(n-6).
%F Empirical g.f.: x*(1 + x - x^2 - 8*x^3 - 10*x^4 - 4*x^5) / (1 - x - 2*x^2 - 5*x^3 + 2*x^4 + 6*x^5 + 4*x^6). - _Colin Barker_, Mar 22 2018
%e Some solutions for n=7:
%e ..0..0. .1..1. .0..0. .0..0. .1..1. .0..0. .0..0. .0..0. .1..1. .1..1
%e ..1..1. .1..1. .1..1. .1..1. .1..1. .1..1. .0..0. .1..1. .1..1. .1..1
%e ..1..1. .1..0. .1..1. .1..1. .0..1. .1..1. .0..0. .1..1. .0..1. .1..0
%e ..0..0. .1..0. .1..0. .0..0. .1..1. .1..0. .1..1. .0..0. .0..1. .1..1
%e ..1..1. .1..1. .1..0. .0..0. .0..1. .1..1. .1..1. .0..0. .1..1. .0..1
%e ..1..1. .1..1. .1..1. .1..1. .1..1. .1..1. .0..0. .0..0. .1..1. .1..1
%e ..0..0. .0..0. .1..1. .1..1. .1..1. .0..0. .0..0. .0..0. .0..0. .1..1
%Y Cf. A296115.
%K nonn
%O 1,2
%A _R. H. Hardin_, Dec 04 2017
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