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%I #4 Feb 19 2016 13:44:23
%S 216,15540,872460,43964700,2085484068,95166487524,4227147007836,
%T 184069947098892,7894012975085748,334480929126425748,
%U 14034341507370527532,584107408947764887164,24145251769444080595908
%N Number of nX4 0..3 arrays with some element plus some horizontally or vertically adjacent neighbor totalling three no more than once.
%C Column 4 of A269109.
%H R. H. Hardin, <a href="/A269105/b269105.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 90*a(n-1) -2559*a(n-2) +24556*a(n-3) -94959*a(n-4) +140442*a(n-5) -69169*a(n-6) for n>7
%e Some solutions for n=2
%e ..3..2..0..2. .3..1..1..0. .2..3..1..3. .3..0..0..2. .0..0..2..3
%e ..2..0..0..1. .2..0..3..1. .2..2..3..3. .3..1..0..0. .0..0..3..1
%Y Cf. A269109.
%K nonn
%O 1,1
%A _R. H. Hardin_, Feb 19 2016
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