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%I #8 Dec 27 2018 06:20:13
%S 49,87,167,299,564,1086,2045,3870,7371,14001,26647,50766,96574,183815,
%T 350088,666497,1268925,2416285,4600654,8759750,16679685,31759384,
%U 60472021,115144725,219245665,417461876,794885812,1513533557,2881900030
%N Number of (n+2) X (2+2) 0..1 arrays with each 3 X 3 subblock having clockwise perimeter pattern 00000001 or 00000101.
%H R. H. Hardin, <a href="/A259766/b259766.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = a(n-1) + a(n-2) + a(n-3) + 2*a(n-4) - 2*a(n-5) + 2*a(n-6) - 4*a(n-7) - 3*a(n-8) + 2*a(n-9) - 4*a(n-10) + 2*a(n-11) for n>12.
%F Empirical g.f.: x*(49 + 38*x + 31*x^2 - 4*x^3 - 87*x^4 - 20*x^5 - 162*x^6 - 67*x^7 + x^8 - 96*x^9 + 78*x^10 - 6*x^11) / (1 - x - x^2 - x^3 - 2*x^4 + 2*x^5 - 2*x^6 + 4*x^7 + 3*x^8 - 2*x^9 + 4*x^10 - 2*x^11). - _Colin Barker_, Dec 27 2018
%e Some solutions for n=4:
%e ..0..0..0..0....0..0..1..0....0..0..0..1....0..1..0..0....0..0..0..1
%e ..0..1..0..0....0..0..0..1....1..0..0..0....1..0..0..0....0..0..0..0
%e ..1..0..0..0....0..0..0..0....0..0..0..0....0..0..0..0....1..0..0..1
%e ..0..0..0..0....1..0..0..0....1..0..0..1....0..0..0..1....0..0..0..0
%e ..1..0..0..1....0..0..0..1....0..0..0..0....0..0..1..0....0..0..0..0
%e ..0..0..0..0....0..0..0..0....0..0..0..0....0..0..0..0....1..0..1..0
%Y Column 2 of A259770.
%K nonn
%O 1,1
%A _R. H. Hardin_, Jul 04 2015
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