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Number of nX4 0..1 arrays with every element unequal to 0, 1, 2, 7 or 8 king-move adjacent elements, with upper left element zero.
1

%I #4 Jun 05 2018 18:28:12

%S 8,5,8,15,38,102,247,617,1559,3892,9739,24416,61132,153073,383397,

%T 960157,2404528,6021899,15081066,37768418,94586143,236878625,

%U 593231091,1485669328,3720663535,9317911688,23335483576,58440647945,146356910517

%N Number of nX4 0..1 arrays with every element unequal to 0, 1, 2, 7 or 8 king-move adjacent elements, with upper left element zero.

%C Column 4 of A305586.

%H R. H. Hardin, <a href="/A305582/b305582.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = a(n-1) +2*a(n-2) +5*a(n-3) -2*a(n-5) -4*a(n-6) for n>8

%e Some solutions for n=5

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

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

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

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

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

%Y Cf. A305586.

%K nonn

%O 1,1

%A _R. H. Hardin_, Jun 05 2018