%I #4 Oct 12 2018 12:26:56
%S 4,28,142,732,3694,18754,94842,480321,2431390,12309913,62320210,
%T 315508545,1597316261,8086701105,40940363689,207267894413,
%U 1049330682760,5312423710470,26895092511498,136161202337290,689340370573277
%N Number of nX3 0..1 arrays with every element unequal to 0, 1, 2, 3 or 5 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.
%C Column 3 of A320402.
%H R. H. Hardin, <a href="/A320397/b320397.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 3*a(n-1) +11*a(n-2) -a(n-3) -8*a(n-4) -a(n-5) -26*a(n-6) -5*a(n-7) +18*a(n-8) +5*a(n-9) -5*a(n-10) -4*a(n-11) -a(n-12) for n>14
%e Some solutions for n=5
%e ..0..0..0. .0..0..1. .0..1..0. .0..1..0. .0..1..0. .0..0..0. .0..1..1
%e ..0..0..0. .1..1..1. .1..1..1. .0..1..1. .1..0..1. .1..1..0. .1..0..1
%e ..0..1..0. .1..1..1. .1..0..0. .0..1..1. .1..1..0. .1..1..0. .1..0..0
%e ..1..0..1. .1..0..0. .1..1..0. .1..1..1. .1..0..1. .1..1..1. .0..0..1
%e ..1..1..1. .1..1..1. .0..0..0. .0..0..0. .0..0..1. .0..1..0. .0..0..1
%Y Cf. A320402.
%K nonn
%O 1,1
%A _R. H. Hardin_, Oct 12 2018
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