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%I #8 Feb 22 2019 10:04:54
%S 5,19,56,198,665,2213,7479,25105,84326,283532,952661,3201517,10759441,
%T 36157455,121511416,408352614,1372308917,4611790689,15498404475,
%U 52083999509,175033735054,588219141252,1976771852673,6643148349849
%N Number of n X 3 0..1 arrays with each 1 adjacent to 0 or 2 king-move neighboring 1s.
%H R. H. Hardin, <a href="/A295776/b295776.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 2*a(n-1) + 3*a(n-2) + 6*a(n-3) - 3*a(n-4) + 2*a(n-5).
%F Empirical g.f.: x*(5 + 9*x + 3*x^2 - x^3 + 2*x^4) / (1 - 2*x - 3*x^2 - 6*x^3 + 3*x^4 - 2*x^5). - _Colin Barker_, Feb 22 2019
%e Some solutions for n=7:
%e ..1..1..0. .0..0..0. .1..0..0. .0..0..0. .0..0..1. .1..0..0. .0..0..0
%e ..0..1..0. .0..0..0. .0..0..0. .0..0..0. .0..0..0. .0..0..1. .0..0..0
%e ..0..0..0. .0..0..0. .0..0..1. .0..1..0. .0..1..1. .0..0..0. .0..0..0
%e ..0..1..1. .0..1..1. .1..0..0. .0..0..0. .0..0..1. .0..1..0. .1..0..0
%e ..0..1..0. .0..1..0. .0..0..1. .1..0..1. .1..0..0. .1..0..1. .0..0..0
%e ..0..0..0. .0..0..0. .1..0..0. .0..0..0. .1..1..0. .1..0..1. .0..1..0
%e ..1..0..1. .0..0..0. .0..0..0. .0..0..0. .0..0..0. .0..1..0. .0..1..1
%Y Column 3 of A295781.
%K nonn
%O 1,1
%A _R. H. Hardin_, Nov 27 2017
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