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%I #8 Dec 30 2018 09:09:57
%S 36,50,96,166,307,540,1015,1786,3304,5862,10877,19316,35609,63526,
%T 116992,209094,383787,687684,1260543,2262114,4138240,7439142,13591813,
%U 24462924,44638225,80433102,146628424,264446262,481653251,869371260,1582318631
%N Number of (n+2) X (1+2) 0..1 arrays with each 3 X 3 subblock having clockwise perimeter pattern 00000001 00010101 or 01010101.
%H R. H. Hardin, <a href="/A261285/b261285.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = a(n-2) + 2*a(n-3) + 4*a(n-4) + 3*a(n-6) - 8*a(n-7) + 9*a(n-8) - 6*a(n-9) - 4*a(n-10) - 4*a(n-11) - 4*a(n-12) for n>13.
%F Empirical g.f.: x*(36 + 50*x + 60*x^2 + 44*x^3 - 33*x^4 - 18*x^5 - 116*x^6 + 106*x^7 - 231*x^8 - 78*x^9 - 72*x^10 - 36*x^11 + 28*x^12) / (1 - x^2 - 2*x^3 - 4*x^4 - 3*x^6 + 8*x^7 - 9*x^8 + 6*x^9 + 4*x^10 + 4*x^11 + 4*x^12). - _Colin Barker_, Dec 30 2018
%e Some solutions for n=4:
%e ..0..0..0....0..0..0....0..1..0....0..0..1....0..1..0....0..0..0....0..0..0
%e ..1..0..1....1..0..0....0..0..1....0..0..0....1..0..1....0..1..0....1..0..1
%e ..0..1..0....0..0..0....0..1..0....1..0..1....0..1..0....0..0..1....0..1..0
%e ..1..0..0....0..0..0....1..0..1....0..1..0....0..0..1....0..1..0....0..0..1
%e ..0..1..0....0..0..1....0..0..0....1..0..1....0..1..0....1..0..1....0..1..0
%e ..0..0..0....0..0..0....0..0..1....0..1..0....0..0..0....0..0..0....1..0..1
%Y Column 1 of A261292.
%K nonn
%O 1,1
%A _R. H. Hardin_, Aug 14 2015
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