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%I #4 Apr 07 2018 17:04:14
%S 4,25,30,66,142,289,599,1268,2660,5558,11659,24470,51293,107533,
%T 225522,472918,991618,2079349,4360310,9143205,19172527,40203428,
%U 84303632,176778210,370690543,777310342,1629961137,3417905349,7167090042
%N Number of 3Xn 0..1 arrays with every element equal to 0, 1, 2 or 5 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.
%C Row 3 of A302415.
%H R. H. Hardin, <a href="/A302416/b302416.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 3*a(n-1) -3*a(n-2) +4*a(n-3) -4*a(n-4) +a(n-5) for n>9
%e Some solutions for n=5
%e ..0..0..1..1..0. .0..1..1..0..0. .0..1..0..1..0. .0..1..0..1..0
%e ..1..0..0..0..1. .0..0..1..0..1. .1..0..0..1..0. .0..1..1..1..1
%e ..1..0..1..0..1. .1..0..1..0..0. .0..1..0..1..1. .1..1..0..0..0
%Y Cf. A302415.
%K nonn
%O 1,1
%A _R. H. Hardin_, Apr 07 2018