%I #4 Jul 15 2018 14:02:04
%S 4,23,99,425,1877,8333,36900,163433,724406,3210961,14232174,63085590,
%T 279639102,1239553378,5494572826,24355881186,107962769031,
%U 478568720832,2121361756337,9403406620066,41682688016275,184767777113249
%N Number of nX3 0..1 arrays with every element unequal to 0, 1, 2, 3, 5, 6 or 7 king-move adjacent elements, with upper left element zero.
%C Column 3 of A316876.
%H R. H. Hardin, <a href="/A316871/b316871.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 5*a(n-1) -a(n-2) +2*a(n-3) -36*a(n-4) -22*a(n-5) +16*a(n-6) +131*a(n-7) +27*a(n-8) -72*a(n-9) -71*a(n-10) +21*a(n-11) +16*a(n-12) -15*a(n-13) -10*a(n-14) -18*a(n-15) -8*a(n-16) for n>17
%e Some solutions for n=5
%e ..0..0..1. .0..0..0. .0..1..1. .0..0..1. .0..1..0. .0..0..0. .0..0..1
%e ..0..0..1. .0..1..1. .0..1..0. .0..0..0. .1..1..1. .1..0..1. .0..0..0
%e ..0..0..1. .1..0..1. .0..0..0. .0..1..1. .1..1..1. .1..1..1. .0..0..0
%e ..0..1..0. .1..1..1. .0..1..0. .1..0..1. .1..0..1. .0..0..1. .0..1..0
%e ..1..1..0. .0..1..0. .1..0..1. .0..1..0. .0..1..0. .0..0..1. .1..0..1
%Y Cf. A316876.
%K nonn
%O 1,1
%A _R. H. Hardin_, Jul 15 2018
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