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%I #8 Feb 22 2019 15:52:35
%S 1,5,11,21,55,125,271,645,1479,3325,7695,17653,40183,92269,211487,
%T 483365,1107591,2537245,5806511,13298005,30454935,69724365,159661375,
%U 365617029,837155239,1916943229,4389542863,10051119797,23015247287,52701125421
%N Number of n X 2 0..1 arrays with each 1 adjacent to 2 or 4 king-move neighboring 1s.
%H R. H. Hardin, <a href="/A296033/b296033.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = a(n-1) + 6*a(n-3) + 4*a(n-5).
%F Empirical g.f.: x*(1 + 4*x + 6*x^2 + 4*x^3 + 4*x^4) / (1 - x - 6*x^3 - 4*x^5). - _Colin Barker_, Feb 22 2019
%e Some solutions for n=5:
%e ..1..1. .1..0. .0..0. .0..1. .1..0. .0..1. .0..0. .1..1. .1..1. .0..0
%e ..1..0. .1..1. .0..0. .1..1. .1..1. .1..1. .0..0. .1..0. .0..1. .0..0
%e ..1..1. .0..0. .0..0. .0..0. .1..1. .0..0. .1..1. .1..1. .1..1. .1..0
%e ..0..0. .1..0. .1..0. .0..1. .1..0. .0..0. .1..0. .1..1. .1..1. .1..1
%e ..0..0. .1..1. .1..1. .1..1. .0..0. .0..0. .0..0. .1..0. .0..1. .0..0
%Y Column 2 of A296039.
%K nonn
%O 1,2
%A _R. H. Hardin_, Dec 03 2017
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