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%I #7 Feb 21 2018 12:51:31
%S 2,8,25,85,286,969,3281,11114,37649,127541,432062,1463673,4958409,
%T 16797346,56903505,192769085,653033942,2212249593,7494324497,
%U 25388138778,86006095793,291358440197,987020046574,3343677195961,11327203768153
%N Number of n X 2 0..1 arrays with no element equal to more than three of its king-move neighbors and with new values introduced in order 0 sequentially upwards.
%C Column 2 of A281344.
%H R. H. Hardin, <a href="/A281338/b281338.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).
%F Empirical g.f.: x*(2 + 2*x - x^2 - 2*x^3 - 6*x^4) / (1 - 3*x - x^2 - 2*x^3 + 2*x^4 + 4*x^5). - _Colin Barker_, Feb 21 2018
%e Some solutions for n=4:
%e ..0..0. .0..0. .0..1. .0..1. .0..1. .0..1. .0..0. .0..1. .0..1. .0..1
%e ..1..0. .1..0. .0..1. .0..1. .1..0. .1..0. .1..0. .0..1. .0..0. .0..1
%e ..0..1. .0..1. .0..1. .0..1. .1..1. .1..0. .0..1. .0..0. .1..1. .1..1
%e ..1..1. .0..1. .0..0. .1..0. .0..0. .1..0. .0..0. .0..1. .0..0. .0..1
%Y Cf. A281344.
%K nonn
%O 1,1
%A _R. H. Hardin_, Jan 20 2017
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