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Number of nX3 0..1 arrays with every element unequal to 0, 1, 2, 3, 4, 7 or 8 king-move adjacent elements, with upper left element zero.
1

%I #4 Jul 21 2018 17:23:09

%S 4,30,142,698,3398,16686,81809,401415,1969107,9660093,47389711,

%T 232481946,1140496397,5594981980,27447541559,134650576212,

%U 660561074466,3240542648641,15897268312271,77987907394984,382588604448738

%N Number of nX3 0..1 arrays with every element unequal to 0, 1, 2, 3, 4, 7 or 8 king-move adjacent elements, with upper left element zero.

%C Column 3 of A317118.

%H R. H. Hardin, <a href="/A317113/b317113.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 3*a(n-1) +10*a(n-2) -a(n-3) -12*a(n-4) +7*a(n-5) -a(n-6) -20*a(n-7) +15*a(n-8) -3*a(n-9) -3*a(n-10) for n>12

%e Some solutions for n=5

%e ..0..1..0. .0..0..0. .0..0..1. .0..0..1. .0..0..0. .0..0..1. .0..0..0

%e ..1..1..1. .1..1..1. .0..1..0. .1..0..0. .0..0..0. .0..1..0. .1..0..0

%e ..1..1..1. .0..1..1. .1..1..1. .0..1..0. .0..1..0. .0..0..0. .1..1..0

%e ..0..0..1. .1..0..1. .0..1..1. .0..0..0. .0..1..0. .1..0..0. .1..1..1

%e ..0..0..0. .0..0..0. .0..1..1. .1..0..0. .0..0..0. .1..1..1. .1..1..1

%Y Cf. A317118.

%K nonn

%O 1,1

%A _R. H. Hardin_, Jul 21 2018