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%I #4 Aug 06 2018 11:49:26
%S 8,20,28,43,72,127,232,432,813,1539,2922,5557,10577,20141,38362,73076,
%T 139212,265212,505263,962600,1833903,3493880,6656412,12681561,
%U 24160471,46029702,87694221,167072053,318300013,606414406,1155320200,2201076948
%N Number of nX4 0..1 arrays with every element unequal to 0, 1 or 2 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.
%C Column 4 of A317764.
%H R. H. Hardin, <a href="/A317760/b317760.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 2*a(n-1) +a(n-2) -2*a(n-3) -a(n-4) +a(n-5) for n>6
%e Some solutions for n=5
%e ..0..1..1..0. .0..0..0..1. .0..0..0..0. .0..0..0..0. .0..1..1..1
%e ..1..1..0..0. .0..0..1..1. .0..0..0..1. .0..0..0..0. .1..1..1..1
%e ..1..0..0..1. .0..1..1..0. .0..0..1..1. .0..0..0..0. .1..1..1..1
%e ..0..0..1..1. .1..1..0..0. .0..1..1..1. .0..0..0..1. .0..0..0..0
%e ..0..1..1..1. .1..0..0..0. .1..1..1..0. .0..0..1..1. .0..0..0..0
%Y Cf. A317764.
%K nonn
%O 1,1
%A _R. H. Hardin_, Aug 06 2018
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