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%I #7 Dec 29 2018 08:24:36
%S 36,48,104,186,297,491,883,1489,2534,4289,7421,12581,21537,36634,
%T 62796,106888,182812,311578,532706,908294,1551949,2647450,4522307,
%U 7716224,13177700,22488756,38401007,65541083,111905468,191009570,326112380
%N Number of (n+2) X (1+2) 0..1 arrays with each 3 X 3 subblock having clockwise perimeter pattern 00010101 00101011 or 01010101.
%H R. H. Hardin, <a href="/A260920/b260920.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = a(n-2) + 3*a(n-4) + 2*a(n-5) + 2*a(n-6) + 3*a(n-7) + a(n-8) for n>10.
%F Empirical g.f.: x*(36 + 48*x + 68*x^2 + 138*x^3 + 85*x^4 + 89*x^5 + 106*x^6 + 28*x^7 + x^9) / (1 - x^2 - 3*x^4 - 2*x^5 - 2*x^6 - 3*x^7 - x^8). - _Colin Barker_, Dec 29 2018
%e Some solutions for n=4:
%e ..1..0..0....0..1..0....0..0..1....0..1..1....0..1..1....1..0..0....1..0..0
%e ..0..0..0....0..0..1....0..0..0....1..1..0....1..0..0....0..1..0....1..0..1
%e ..1..0..1....0..1..0....1..0..1....0..1..0....0..1..0....1..0..1....0..1..0
%e ..0..1..0....1..0..1....0..1..0....1..0..1....1..0..1....0..1..0....0..0..1
%e ..1..0..0....0..1..0....0..0..1....0..0..1....0..0..0....1..0..1....1..1..0
%e ..0..1..0....1..0..0....0..1..0....1..0..0....1..0..0....0..0..0....1..0..1
%Y Column 1 of A260927.
%K nonn
%O 1,1
%A _R. H. Hardin_, Aug 04 2015
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