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A303890 Number of nX2 0..1 arrays with every element unequal to 1, 2, 3 or 4 king-move adjacent elements, with upper left element zero. 8

%I

%S 1,7,23,86,313,1145,4184,15293,55895,204294,746685,2729101,9974744,

%T 36457249,133249635,487021534,1780042209,6505975697,23779053976,

%U 86911392597,317657303391,1161023421462,4243489354069,15509766267621

%N Number of nX2 0..1 arrays with every element unequal to 1, 2, 3 or 4 king-move adjacent elements, with upper left element zero.

%C Column 2 of A303896.

%H R. H. Hardin, <a href="/A303890/b303890.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 3*a(n-1) +a(n-2) +4*a(n-3) +4*a(n-4)

%e Some solutions for n=5

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

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

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

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

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

%Y Cf. A303896.

%K nonn

%O 1,2

%A _R. H. Hardin_, May 02 2018

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Last modified September 27 07:24 EDT 2022. Contains 357052 sequences. (Running on oeis4.)