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A303684 Number of nX2 0..1 arrays with every element unequal to 2, 3 or 4 king-move adjacent elements, with upper left element zero. 12

%I

%S 0,3,5,18,61,209,702,2381,8069,27330,92581,313641,1062502,3599373,

%T 12193421,41307034,139933701,474046225,1605902110,5440232205,

%U 18429595637,62432996082,211501059173,716491292025,2427220807318,8222571457613

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

%C Column 2 of A303690.

%H R. H. Hardin, <a href="/A303684/b303684.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 3*a(n-1) +a(n-2) +2*a(n-3) -2*a(n-4) -4*a(n-5) for n>6

%e Some solutions for n=5

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

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

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

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

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

%Y Cf. A303690.

%K nonn

%O 1,2

%A _R. H. Hardin_, Apr 28 2018

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Last modified October 24 20:31 EDT 2021. Contains 348233 sequences. (Running on oeis4.)