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%I #4 Oct 11 2018 14:08:47
%S 4,32,228,1612,11396,80568,569608,4027076,28471056,201287740,
%T 1423085756,10061085036,71130943216,502889207744,3555380314548,
%U 25136210891824,177710692555988,1256398205148780,8882619425973796,62799300049416872
%N Number of nX3 0..1 arrays with every element unequal to 0, 1, 2, 3 or 4 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.
%C Column 3 of A320371.
%H R. H. Hardin, <a href="/A320366/b320366.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 8*a(n-1) -7*a(n-2) +3*a(n-3)
%e Some solutions for n=5
%e ..0..1..0. .0..1..1. .0..1..1. .0..0..1. .0..0..0. .0..1..0. .0..0..0
%e ..1..1..0. .1..0..0. .1..0..0. .0..0..0. .1..0..1. .0..0..1. .1..1..0
%e ..0..0..1. .0..0..0. .0..1..1. .1..0..1. .0..1..0. .0..0..1. .0..1..1
%e ..0..1..1. .0..0..0. .1..1..0. .0..0..1. .0..1..0. .1..1..1. .0..1..1
%e ..1..0..1. .0..1..1. .1..1..0. .1..0..0. .1..1..0. .1..0..0. .0..1..1
%Y Cf. A320371.
%K nonn
%O 1,1
%A _R. H. Hardin_, Oct 11 2018
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