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Number of nX3 0..1 arrays with every element equal to 1, 2, 4, 5, 7 or 8 king-move adjacent elements, with upper left element zero.
1

%I #4 Feb 13 2018 11:15:11

%S 1,7,15,25,47,113,265,621,1473,3443,8093,19107,45119,106635,251959,

%T 595465,1407719,3328477,7871557,18617533,44037365,104173407,246445341,

%U 583054499,1379487511,3263943687,7722913379,18273883713,43240415955

%N Number of nX3 0..1 arrays with every element equal to 1, 2, 4, 5, 7 or 8 king-move adjacent elements, with upper left element zero.

%C Column 3 of A299574.

%H R. H. Hardin, <a href="/A299569/b299569.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 4*a(n-1) -3*a(n-2) -a(n-3) -6*a(n-4) +11*a(n-5) -8*a(n-6) +4*a(n-7) -7*a(n-8) +16*a(n-9) +5*a(n-10) -3*a(n-11) -18*a(n-12) +a(n-13) +6*a(n-14) for n>15

%e Some solutions for n=8

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

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

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

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

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

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

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

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

%Y Cf. A299574.

%K nonn

%O 1,2

%A _R. H. Hardin_, Feb 13 2018