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%I #4 Aug 07 2018 22:05:10
%S 1,16,35,135,356,1113,3150,9484,27522,81798,239572,707803,2080838,
%T 6134691,18056895,53200116,156648460,461423021,1358857346,4002288009,
%U 11787108436,34715792064,102243257032,301126862896,886870040361
%N Number of nX3 0..1 arrays with every element unequal to 1, 2 or 3 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.
%C Column 3 of A317823.
%H R. H. Hardin, <a href="/A317818/b317818.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = a(n-1) +7*a(n-2) +2*a(n-3) -10*a(n-4) -14*a(n-5) -16*a(n-6) -25*a(n-7) +36*a(n-8) +42*a(n-9) -26*a(n-10) +62*a(n-11) +10*a(n-12) -28*a(n-13) +20*a(n-14) -16*a(n-15) +4*a(n-16) for n>18
%e Some solutions for n=5
%e ..0..1..1. .0..1..1. .0..1..0. .0..0..1. .0..0..1. .0..1..0. .0..0..0
%e ..1..0..0. .1..0..0. .1..0..0. .1..0..0. .1..0..0. .1..0..1. .1..1..1
%e ..0..0..1. .0..0..1. .0..1..1. .1..0..0. .1..0..1. .0..0..1. .0..1..1
%e ..1..1..1. .0..1..0. .1..1..0. .0..0..1. .0..1..1. .0..0..1. .0..1..0
%e ..0..0..0. .1..1..0. .0..0..1. .0..1..0. .1..0..0. .1..0..0. .0..1..0
%Y Cf. A317823.
%K nonn
%O 1,2
%A _R. H. Hardin_, Aug 07 2018
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