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%I #4 Feb 13 2016 18:19:46
%S 24,104,332,1202,4158,14308,48460,162722,541744,1791504,5889586,
%T 19264864,62738690,203528858,658003018,2120809106,6816832928,
%U 21856821554,69922091542,223229394256,711333766468,2262803472594,7186710244256
%N Number of nX3 0..2 arrays with some element plus some horizontally, vertically or antidiagonally adjacent neighbor totalling two not more than once.
%C Column 3 of A268809.
%H R. H. Hardin, <a href="/A268804/b268804.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 2*a(n-1) +9*a(n-2) -2*a(n-3) -33*a(n-4) -42*a(n-5) -14*a(n-6) +10*a(n-7) +8*a(n-8) -a(n-10) for n>12
%e Some solutions for n=4
%e ..0..1..2. .0..1..1. .2..2..1. .1..2..2. .1..0..0. .2..0..0. .2..2..2
%e ..0..0..1. .0..0..0. .1..2..2. .2..2..1. .0..1..0. .1..0..0. .2..1..1
%e ..1..0..0. .0..0..0. .2..1..2. .1..2..2. .0..0..1. .0..1..0. .2..2..2
%e ..0..0..0. .1..0..1. .1..2..2. .2..1..1. .0..1..2. .0..0..0. .2..2..1
%Y Cf. A268809.
%K nonn
%O 1,1
%A _R. H. Hardin_, Feb 13 2016
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