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Number of nX7 0..1 arrays with every element equal to 0, 1, 4 or 6 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.
1

%I #4 Apr 11 2018 12:27:42

%S 21,23,94,217,661,2013,6311,19497,60253,186797,578385,1790605,5545571,

%T 17172267,53173813,164661159,509890659,1578918645,4889288817,

%U 15140189411,46883090855,145178205375,449559001303,1392104734057,4310792424591

%N Number of nX7 0..1 arrays with every element equal to 0, 1, 4 or 6 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.

%C Column 7 of A302680.

%H R. H. Hardin, <a href="/A302679/b302679.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = a(n-1) +a(n-2) +12*a(n-3) +14*a(n-4) +10*a(n-5) -9*a(n-6) -26*a(n-7) +2*a(n-8) +18*a(n-9) +6*a(n-10) -4*a(n-12) for n>19

%e Some solutions for n=5

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

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

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

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

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

%Y Cf. A302680.

%K nonn

%O 1,1

%A _R. H. Hardin_, Apr 11 2018