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%I #8 Dec 26 2018 12:00:06
%S 62,136,374,868,1882,4456,10570,24150,55686,130032,301564,697220,
%T 1617512,3753468,8697990,20161962,46756582,108404418,251306798,
%U 582661346,1350925528,3132018192,7261427776,16835543314,39032675868,90495655752
%N Number of (n+2) X (4+2) 0..1 arrays with each 3 X 3 subblock having clockwise perimeter pattern 00010101 or 01010101.
%H R. H. Hardin, <a href="/A259738/b259738.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = a(n-1) + 4*a(n-3) + 5*a(n-4) + 3*a(n-5) + 5*a(n-6) + a(n-7) - 4*a(n-8) - a(n-9) + a(n-10) for n>11.
%F Empirical g.f.: 2*x*(31 + 37*x + 119*x^2 + 123*x^3 + 80*x^4 + 106*x^5 + 27*x^6 - 76*x^7 - 30*x^8 + 16*x^9 + 3*x^10) / (1 - x - 4*x^3 - 5*x^4 - 3*x^5 - 5*x^6 - x^7 + 4*x^8 + x^9 - x^10). - _Colin Barker_, Dec 26 2018
%e Some solutions for n=4:
%e ..0..0..0..1..0..1....0..0..1..0..1..0....1..0..1..0..1..0....0..1..0..1..0..1
%e ..1..0..1..0..1..0....0..0..0..1..0..0....0..0..0..1..0..1....1..0..1..0..1..0
%e ..0..1..0..1..0..1....1..0..1..0..1..0....1..0..1..0..0..0....0..0..0..1..0..1
%e ..1..0..1..0..1..0....0..1..0..1..0..1....0..1..0..1..0..1....1..0..1..0..1..0
%e ..0..1..0..1..0..1....1..0..1..0..0..0....1..0..1..0..1..0....0..1..0..1..0..0
%e ..1..0..1..0..1..0....0..1..0..1..0..0....0..1..0..1..0..0....0..0..1..0..1..0
%Y Column 4 of A259742.
%K nonn
%O 1,1
%A _R. H. Hardin_, Jul 04 2015
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