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%I #4 Aug 21 2018 13:18:11
%S 0,1,4,18,86,413,1975,9474,45415,217714,1043722,5003565,23986950,
%T 114992767,551272103,2642783040,12669427963,60736883262,291170919400,
%U 1395865242913,6691738929130,32080009243747,153790666966961
%N Number of nX3 0..1 arrays with every element unequal to 2, 3, 4 or 5 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.
%C Column 3 of A318222.
%H R. H. Hardin, <a href="/A318217/b318217.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 5*a(n-1) -a(n-2) +a(n-3) -5*a(n-4) +3*a(n-5) -3*a(n-6) +a(n-7) -8*a(n-8) -4*a(n-10) +2*a(n-11)
%e Some solutions for n=5
%e ..0..1..0. .0..1..0. .0..1..0. .0..1..1. .0..1..1. .0..1..0. .0..1..1
%e ..1..1..0. .1..1..1. .1..0..1. .1..0..0. .1..0..0. .1..0..1. .1..0..0
%e ..0..1..1. .0..0..0. .1..0..0. .1..0..1. .0..1..1. .1..1..0. .0..0..1
%e ..0..0..1. .1..1..1. .1..1..1. .0..0..0. .1..1..0. .0..0..1. .1..0..1
%e ..1..1..0. .0..1..0. .0..1..0. .1..0..1. .0..0..1. .1..1..0. .0..1..0
%Y Cf. A318222.
%K nonn
%O 1,3
%A _R. H. Hardin_, Aug 21 2018
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