%I #8 Dec 29 2018 07:08:03
%S 40,75,193,337,582,1350,2732,5037,10549,21615,41842,84846,172576,
%T 341567,686447,1387291,2770696,5557618,11190652,22426331,44981821,
%U 90410789,181399432,363944476,730917000,1467035943,2944001797,5910524039
%N Number of (n+2) X (1+2) 0..1 arrays with each 3 X 3 subblock having clockwise perimeter pattern 00000001 00000011 or 00010001.
%H R. H. Hardin, <a href="/A260537/b260537.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) - 2*a(n-4) - 5*a(n-5) - 6*a(n-6) - a(n-7) + 2*a(n-8) + 2*a(n-9) for n>10.
%F Empirical g.f.: x*(40 + 35*x + 78*x^2 - 131*x^3 - 243*x^4 - 184*x^5 + 116*x^6 + 174*x^7 + 32*x^8 - 36*x^9) / (1 - x - x^2 - 5*x^3 + 2*x^4 + 5*x^5 + 6*x^6 + x^7 - 2*x^8 - 2*x^9). - _Colin Barker_, Dec 29 2018
%e Some solutions for n=4:
%e ..1..0..0....0..0..0....0..0..1....1..0..0....0..0..0....0..0..0....0..0..1
%e ..0..0..0....1..0..0....0..0..0....0..1..0....1..0..0....0..0..1....0..1..1
%e ..0..0..1....1..0..0....0..0..0....0..0..0....1..0..0....0..0..0....0..0..0
%e ..0..0..1....0..0..0....1..0..0....0..0..0....0..0..0....0..0..0....0..0..0
%e ..0..0..0....0..0..1....0..0..0....0..1..1....0..0..1....0..1..0....1..0..0
%e ..0..0..0....0..0..1....0..0..1....0..0..1....0..0..0....0..0..1....1..0..0
%Y Column 1 of A260544.
%K nonn
%O 1,1
%A _R. H. Hardin_, Jul 28 2015
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