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%I #4 Feb 06 2018 13:35:08
%S 1,7,15,29,63,199,593,1657,4689,13395,38357,109855,313667,896417,
%T 2563517,7330205,20956899,59914557,171302635,489779503,1400327457,
%U 4003663145,11446878297,32727841823,93572301793,267532776375,764903730599
%N Number of nX3 0..1 arrays with every element equal to 1, 2, 4, 5, 6 or 7 king-move adjacent elements, with upper left element zero.
%C Column 3 of A299314.
%H R. H. Hardin, <a href="/A299309/b299309.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 4*a(n-1) -3*a(n-2) +a(n-3) -3*a(n-4) -6*a(n-5) -8*a(n-6) +18*a(n-7) +27*a(n-8) -18*a(n-9) +15*a(n-10) -55*a(n-11) +21*a(n-12) -6*a(n-13) +14*a(n-14) +2*a(n-15) -2*a(n-16) for n>17
%e Some solutions for n=6
%e ..0..1..1. .0..1..0. .0..1..0. .0..1..0. .0..1..0. .0..1..1. .0..1..1
%e ..0..0..1. .1..0..0. .1..0..1. .0..1..0. .0..0..1. .0..0..1. .0..0..1
%e ..0..0..0. .0..0..0. .0..0..0. .1..1..1. .0..0..0. .0..0..0. .0..0..0
%e ..0..0..0. .0..0..0. .0..0..0. .1..1..1. .0..0..0. .0..0..0. .0..0..0
%e ..1..0..1. .1..0..1. .0..0..1. .1..1..0. .1..0..0. .1..0..0. .0..0..1
%e ..1..0..1. .0..1..0. .0..1..0. .1..0..0. .0..1..0. .0..1..0. .0..1..1
%Y Cf. A299314.
%K nonn
%O 1,2
%A _R. H. Hardin_, Feb 06 2018