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%I #8 Dec 27 2018 11:58:25
%S 67,146,439,1187,3227,8964,24719,67952,187266,516133,1421669,3916441,
%T 10790266,29726787,81895288,225619582,621575781,1712418521,4717655719,
%U 12996990098,35806276733,98645103102,271764008258,748700872883
%N Number of (n+2) X (2+2) 0..1 arrays with each 3 X 3 subblock having clockwise perimeter pattern 00000000 00000001 or 00001001.
%H R. H. Hardin, <a href="/A259956/b259956.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = a(n-1) + 2*a(n-2) + 6*a(n-3) + 5*a(n-4) + a(n-5) - 2*a(n-6) - 2*a(n-7) - a(n-8) for n>9.
%F Empirical g.f.: x*(67 + 79*x + 159*x^2 + 54*x^3 - 49*x^4 - 68*x^5 - 28*x^6 - 5*x^7 + 7*x^8) / (1 - x - 2*x^2 - 6*x^3 - 5*x^4 - x^5 + 2*x^6 + 2*x^7 + x^8). - _Colin Barker_, Dec 27 2018
%e Some solutions for n=4:
%e ..0..0..0..0....0..0..0..0....1..0..0..0....0..0..0..0....0..1..0..0
%e ..0..0..0..0....1..0..0..1....0..0..0..0....0..0..0..0....0..0..0..1
%e ..0..0..0..1....0..0..0..0....0..0..0..1....0..0..0..1....0..0..0..0
%e ..0..0..0..0....0..0..0..0....0..0..0..0....1..0..0..0....0..0..1..0
%e ..0..0..0..0....0..1..0..0....1..0..0..0....0..0..1..0....0..0..0..0
%e ..0..1..0..0....0..0..0..0....0..0..0..0....0..0..0..1....0..0..0..1
%Y Column 2 of A259962.
%K nonn
%O 1,1
%A _R. H. Hardin_, Jul 10 2015
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