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Number of nX3 0..1 arrays with no 1 equal to more than one of its king-move neighbors, with the exception of exactly one element.
1

%I #4 Feb 21 2017 08:40:25

%S 1,8,73,318,1747,8216,38027,173722,773529,3412416,14880845,64319686,

%T 276057515,1177345064,4994757435,21091941082,88706514017,371741444080,

%U 1552891025645,6468454612966,26874623008899,111396556833528

%N Number of nX3 0..1 arrays with no 1 equal to more than one of its king-move neighbors, with the exception of exactly one element.

%C Column 3 of A282791.

%H R. H. Hardin, <a href="/A282786/b282786.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 4*a(n-1) +8*a(n-2) -8*a(n-3) -78*a(n-4) -72*a(n-5) -16*a(n-6) +64*a(n-7) -33*a(n-8) +52*a(n-9) -24*a(n-10) +8*a(n-11) -4*a(n-12)

%e Some solutions for n=4

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

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

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

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

%Y Cf. A282791.

%K nonn

%O 1,2

%A _R. H. Hardin_, Feb 21 2017