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A304843 Number of nX3 0..1 arrays with every element unequal to 0, 1, 2, 4 or 7 king-move adjacent elements, with upper left element zero. 1

%I

%S 4,12,25,51,165,419,1009,2697,7091,18147,46901,122403,317379,820951,

%T 2131357,5532371,14340367,37190407,96488757,250257339,649031555,

%U 1683483587,4366629269,11325556739,29375297911,76192462975,197622279245

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

%C Column 3 of A304848.

%H R. H. Hardin, <a href="/A304843/b304843.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = a(n-1) +2*a(n-2) +8*a(n-3) +a(n-4) -9*a(n-5) -26*a(n-6) -6*a(n-7) +6*a(n-8) +16*a(n-9) +2*a(n-10) +6*a(n-11) for n>12

%e Some solutions for n=5

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

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

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

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

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

%Y Cf. A304848.

%K nonn

%O 1,1

%A _R. H. Hardin_, May 19 2018

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Last modified October 28 06:36 EDT 2021. Contains 348315 sequences. (Running on oeis4.)