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%I #7 Dec 28 2018 14:00:29
%S 48,99,256,635,1598,4027,10110,25421,63884,160475,403392,1013853,
%T 2547460,6402009,16089526,40433015,101609368,255352867,641716970,
%U 1612668111,4052732014,10184756245,25594885072,64321450263,161643568800
%N Number of (n+2) X (1+2) 0..1 arrays with each 3 X 3 subblock having clockwise perimeter pattern 00000001 00000101 or 00001001.
%H R. H. Hardin, <a href="/A260241/b260241.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 2*a(n-1) - 2*a(n-2) + 9*a(n-3) - 4*a(n-4) + 9*a(n-5) - 9*a(n-6) for n>7.
%F Empirical g.f.: x*(48 + 3*x + 154*x^2 - 111*x^3 + 141*x^4 - 239*x^5 + 102*x^6) / (1 - 2*x + 2*x^2 - 9*x^3 + 4*x^4 - 9*x^5 + 9*x^6). - _Colin Barker_, Dec 28 2018
%e Some solutions for n=4:
%e ..0..0..0....1..0..0....0..0..0....0..1..0....0..0..0....0..1..0....0..0..0
%e ..1..0..0....0..0..1....1..0..0....0..1..0....0..0..0....0..1..0....0..0..1
%e ..0..1..0....0..0..0....0..1..0....0..0..1....0..1..0....0..0..0....0..1..0
%e ..0..0..0....0..1..0....1..0..0....0..0..0....0..0..1....1..0..0....0..1..0
%e ..0..0..0....0..1..0....0..0..0....0..0..0....0..0..0....0..1..0....0..0..0
%e ..0..1..0....1..0..0....0..1..0....0..1..0....0..0..0....0..1..0....0..0..1
%Y Column 1 of A260248.
%K nonn
%O 1,1
%A _R. H. Hardin_, Jul 20 2015
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