%I #4 Aug 10 2018 10:30:21
%S 0,1,4,13,59,252,1074,4633,19933,85732,368847,1586817,6826551,
%T 29368380,126345008,543545426,2338372742,10059853024,43278232785,
%U 186186164251,800986675100,3445904026216,14824534451888,63776245668953
%N Number of nX3 0..1 arrays with every element unequal to 2, 3 or 4 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.
%C Column 3 of A317896.
%H R. H. Hardin, <a href="/A317891/b317891.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 4*a(n-1) +8*a(n-3) -10*a(n-4) +3*a(n-5) -17*a(n-6) -7*a(n-7) -21*a(n-8) +6*a(n-9) +10*a(n-10) +4*a(n-11) -18*a(n-12) -21*a(n-13) -9*a(n-14) -a(n-15) +2*a(n-16) for n>18
%e Some solutions for n=5
%e ..0..1..0. .0..1..1. .0..1..0. .0..1..1. .0..1..0. .0..1..0. .0..1..0
%e ..1..0..1. .1..0..0. .1..1..0. .1..0..0. .1..1..0. .1..1..0. .1..0..1
%e ..0..1..0. .0..1..0. .0..1..0. .0..1..1. .0..0..1. .0..0..1. .1..0..0
%e ..1..1..1. .1..1..1. .0..1..1. .0..1..0. .1..0..1. .0..1..0. .0..0..1
%e ..0..1..0. .0..1..0. .0..1..0. .1..0..1. .0..1..0. .1..0..1. .1..1..0
%Y Cf. A317896.
%K nonn
%O 1,3
%A _R. H. Hardin_, Aug 10 2018