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%I #7 Jul 11 2018 22:07:04
%S 8,6,7,20,30,76,217,509,1189,3034,7569,18274,44932,111561,274057,
%T 672217,1657278,4083105,10038822,24702412,60827449,149699125,
%U 368356029,906653234,2231584641,5492001706,13516457764,33267138281,81875898241
%N Number of 4Xn 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 Row 4 of A302680.
%H R. H. Hardin, <a href="/A302682/b302682.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = a(n-1) +a(n-2) +5*a(n-3) +5*a(n-4) -3*a(n-5) -3*a(n-6) +2*a(n-7) for n>11
%e Some solutions for n=5
%e ..0..1..1..1..0. .0..1..0..0..0. .0..1..1..1..0. .0..1..0..1..0
%e ..0..1..0..1..0. .0..1..0..1..0. .0..1..0..1..0. .0..1..0..1..0
%e ..0..1..0..0..0. .0..1..0..1..0. .0..0..0..1..0. .0..1..0..1..0
%e ..0..1..0..1..0. .0..1..0..1..0. .0..1..0..1..0. .0..1..0..1..0
%Y Cf. A302680.
%K nonn
%O 1,1
%A _R. H. Hardin_, Apr 11 2018
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