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%I #10 Dec 27 2018 11:54:00
%S 60,170,549,1507,4128,11933,34337,97374,277073,791655,2258776,6438153,
%T 18360749,52375446,149376869,426006811,1215002568,3465304429,
%U 9883190601,28187259534,80391677785,229281523567,653922541496,1865020964353
%N Number of (n+2) X (2+2) 0..1 arrays with each 3 X 3 subblock having clockwise perimeter pattern 00000000 00000001 or 00000101.
%H R. H. Hardin, <a href="/A259946/b259946.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 2*a(n-1) + 2*a(n-2) + a(n-3) + 6*a(n-4) - 14*a(n-5) - 4*a(n-6) + 2*a(n-7) - 4*a(n-8) + 4*a(n-9) for n>10.
%F Empirical g.f.: x*(60 + 50*x + 89*x^2 + 9*x^3 - 514*x^4 - 66*x^5 + 34*x^6 - 90*x^7 + 144*x^8 - 12*x^9) / ((1 + x - x^2)*(1 - 3*x + 2*x^2 - 6*x^3 + 2*x^4 + 6*x^5 + 4*x^7)). - _Colin Barker_, Dec 27 2018
%e Some solutions for n=4:
%e ..0..1..0..0....0..0..0..0....0..0..1..0....0..0..0..0....1..0..0..0
%e ..1..0..0..0....0..0..0..0....0..0..0..1....1..0..0..0....0..0..0..1
%e ..0..0..0..0....1..0..0..1....0..0..0..0....0..0..0..0....1..0..0..0
%e ..0..0..0..0....0..0..0..0....0..0..0..0....0..0..0..0....0..0..0..1
%e ..1..0..0..1....0..0..0..1....0..0..1..0....0..0..0..0....0..0..0..0
%e ..0..0..0..0....1..0..0..0....0..0..0..1....0..0..1..0....1..0..0..1
%Y Column 2 of A259952.
%K nonn
%O 1,1
%A _R. H. Hardin_, Jul 10 2015
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