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A303681 Number of nX7 0..1 arrays with every element unequal to 0, 1 or 3 king-move adjacent elements, with upper left element zero. 1

%I

%S 21,103,57,90,150,245,367,509,697,957,1311,1851,2671,3869,5547,7907,

%T 11275,16101,22959,32717,46663,66633,95139,135763,193701,276435,

%U 394533,563013,803377,1146445,1636117,2334893,3331971,4754851,6785501,9683407

%N Number of nX7 0..1 arrays with every element unequal to 0, 1 or 3 king-move adjacent elements, with upper left element zero.

%C Column 7 of A303682.

%H R. H. Hardin, <a href="/A303681/b303681.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = a(n-1) +a(n-4) +a(n-8) for n>14

%e Some solutions for n=5

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

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

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

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

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

%Y Cf. A303682.

%K nonn

%O 1,1

%A _R. H. Hardin_, Apr 28 2018

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Last modified September 24 14:16 EDT 2021. Contains 347643 sequences. (Running on oeis4.)