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%I #8 Dec 27 2018 08:42:28
%S 34,67,215,499,936,2212,5352,11529,25397,58793,132494,294066,664222,
%T 1503071,3370883,7574191,17082212,38445840,86429444,194563077,
%U 438038913,985523653,2217627370,4991511166,11233246170,25277953979,56888391919
%N Number of (n+2) X (1+2) 0..1 arrays with each 3 X 3 subblock having clockwise perimeter pattern 00000000 00000001 or 00000011.
%H R. H. Hardin, <a href="/A259887/b259887.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = a(n-1) + 5*a(n-3) + 3*a(n-4).
%F Empirical g.f.: x*(34 + 33*x + 148*x^2 + 114*x^3) / (1 - x - 5*x^3 - 3*x^4). - _Colin Barker_, Dec 27 2018
%e Some solutions for n=4:
%e ..1..1..0....0..1..1....0..0..0....0..0..1....0..0..0....1..1..0....1..0..0
%e ..0..0..0....0..1..0....0..0..0....0..0..0....0..0..0....0..0..0....0..1..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..1..1....0..0..0....0..0..0....0..0..0....0..0..0....0..0..0....0..0..0
%e ..0..0..0....1..1..0....0..0..0....0..1..1....0..0..0....0..0..0....0..0..0
%e ..0..0..0....0..0..0....1..1..0....0..0..0....0..1..1....0..0..1....0..1..0
%Y Column 1 of A259894.
%K nonn
%O 1,1
%A _R. H. Hardin_, Jul 07 2015