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%I #7 Jan 18 2019 14:41:12
%S 13,76,521,3288,20400,123976,742688,4397376,25791040,150081504,
%T 867569920,4986765312,28523566592,162453499008,921756644864,
%U 5212543265792,29388948548608,165253519908352,926962234179584,5188178346090496
%N Number of n X 4 binary arrays with some element plus some horizontally, diagonally or antidiagonally adjacent neighbor totalling two not more than once.
%H R. H. Hardin, <a href="/A269071/b269071.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 12*a(n-1) - 40*a(n-2) + 8*a(n-3) + 92*a(n-4) - 32*a(n-5) - 64*a(n-6) for n>7.
%F Empirical g.f.: x*(13 - 80*x + 129*x^2 - 28*x^3 - 20*x^4 - 48*x^5 + 4*x^6) / (1 - 6*x + 2*x^2 + 8*x^3)^2. - _Colin Barker_, Jan 18 2019
%e Some solutions for n=4:
%e ..1..1..0..0. .1..0..0..0. .0..0..1..0. .0..0..0..0. .0..0..0..1
%e ..0..0..0..0. .0..0..1..0. .1..0..1..0. .0..0..1..0. .1..0..0..0
%e ..1..0..0..0. .0..0..0..0. .0..0..0..0. .0..0..0..0. .0..1..0..0
%e ..0..0..0..1. .0..0..1..1. .0..0..0..0. .0..0..0..0. .0..1..0..1
%Y Column 4 of A269075.
%K nonn
%O 1,1
%A _R. H. Hardin_, Feb 19 2016
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