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%I #8 Dec 28 2018 09:06:22
%S 48,85,206,472,1116,2575,6068,14096,33044,76925,180064,419884,981640,
%T 2290567,5352572,12495004,29189140,68152069,159185904,371714924,
%U 868161704,2027353439,4734819476,11057193964,25823175228,60305591933
%N Number of (n+2) X (1+2) 0..1 arrays with each 3 X 3 subblock having clockwise perimeter pattern 00000001 00000101 or 00010101.
%H R. H. Hardin, <a href="/A260099/b260099.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 2*a(n-2) + 2*a(n-3) + 11*a(n-4) + 6*a(n-5) + 2*a(n-6) + 6*a(n-7) - 8*a(n-8) + 2*a(n-9) for n>10.
%F Empirical g.f.: x*(48 + 85*x + 110*x^2 + 206*x^3 + 6*x^4 - 4*x^5 + 20*x^6 - 172*x^7 + 112*x^8 - 20*x^9) / (1 - 2*x^2 - 2*x^3 - 11*x^4 - 6*x^5 - 2*x^6 - 6*x^7 + 8*x^8 - 2*x^9). - _Colin Barker_, Dec 28 2018
%e Some solutions for n=4:
%e ..0..0..0....0..0..0....1..0..1....0..1..0....1..0..1....0..1..0....0..0..1
%e ..1..0..1....1..0..1....0..1..0....0..0..1....0..0..0....0..0..1....0..0..0
%e ..0..1..0....0..1..0....1..0..0....0..1..0....0..0..1....0..0..0....0..0..1
%e ..0..0..0....1..0..0....0..0..0....0..0..0....0..1..0....1..0..1....0..0..0
%e ..0..0..0....0..0..0....1..0..0....0..0..0....1..0..1....0..1..0....1..0..1
%e ..1..0..0....1..0..0....0..0..0....0..1..0....0..0..0....1..0..0....0..1..0
%Y Column 1 of A260106.
%K nonn
%O 1,1
%A _R. H. Hardin_, Jul 16 2015
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