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%I #4 Feb 20 2016 10:30:44
%S 64,1740,25572,400428,5877228,84310620,1184381844,16385570076,
%T 223935582828,3030348558252,40673437553748,542180347359564,
%U 7185077761974828,94737850175764476,1243661129422894356
%N Number of 3Xn 0..3 arrays with some element plus some horizontally, diagonally or antidiagonally adjacent neighbor totalling three no more than once.
%C Row 3 of A269201.
%H R. H. Hardin, <a href="/A269203/b269203.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 24*a(n-1) -130*a(n-2) -248*a(n-3) +935*a(n-4) +272*a(n-5) -1768*a(n-6) +960*a(n-7) -144*a(n-8)
%e Some solutions for n=3
%e ..1..3..3. .1..3..1. .1..2..0. .0..0..0. .2..0..3. .1..1..1. .3..3..3
%e ..3..1..1. .2..3..2. .3..1..0. .0..1..1. .1..3..1. .3..1..3. .3..3..3
%e ..1..1..3. .2..3..1. .3..2..0. .3..3..3. .2..0..1. .1..2..0. .2..3..1
%Y Cf. A269201.
%K nonn
%O 1,1
%A _R. H. Hardin_, Feb 20 2016