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%I #7 Dec 28 2018 09:06:33
%S 58,128,342,730,1626,3928,8998,20376,47424,109650,251290,579658,
%T 1338500,3080858,7097716,16367912,37715574,86898450,200293226,
%U 461601736,1063705902,2451421760,5649587496,13019565474,30004282786,69147284586
%N Number of (n+2) X (2+2) 0..1 arrays with each 3 X 3 subblock having clockwise perimeter pattern 00010101 01010101 or 01010111.
%H R. H. Hardin, <a href="/A260132/b260132.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = a(n-1) + a(n-2) + 5*a(n-3) + a(n-4) - 3*a(n-5) - 3*a(n-6) for n>7.
%F Empirical g.f.: 2*x*(29 + 35*x + 78*x^2 - 15*x^3 - 72*x^4 - 46*x^5 + 5*x^6) / (1 - x - x^2 - 5*x^3 - x^4 + 3*x^5 + 3*x^6). - _Colin Barker_, Dec 28 2018
%e Some solutions for n=4:
%e ..1..0..1..0....0..0..1..1....1..0..1..0....0..1..0..1....1..0..0..0
%e ..0..1..0..0....0..1..0..1....1..1..0..1....0..0..1..0....0..1..0..1
%e ..1..0..1..0....1..0..1..0....1..0..1..0....0..1..0..1....1..0..1..0
%e ..1..1..0..1....0..1..0..1....0..1..0..1....1..0..1..0....0..1..0..1
%e ..1..0..1..0....1..0..1..0....0..0..1..0....1..1..0..1....1..0..0..0
%e ..0..1..0..1....1..1..0..0....0..1..0..1....1..0..1..0....0..1..0..1
%Y Column 2 of A260138.
%K nonn
%O 1,1
%A _R. H. Hardin_, Jul 17 2015
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