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%I #4 Aug 01 2015 06:09:53
%S 48,82,188,364,644,1320,2584,4842,9412,18210,35192,68158,130812,
%T 253334,491376,945170,1825292,3533066,6818232,13167414,25439060,
%U 49131310,94931752,183337586,354061772,684091450,1321342040,2551947046,4929738068
%N Number of (n+2)X(1+2) 0..1 arrays with each 3X3 subblock having clockwise perimeter pattern 00000001 00000011 or 00010101
%C Column 1 of A260841
%H R. H. Hardin, <a href="/A260834/b260834.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 4*a(n-3) +3*a(n-4) +4*a(n-5) +12*a(n-8) +12*a(n-9) -8*a(n-11) -12*a(n-12) -12*a(n-13) -8*a(n-14) for n>15
%e Some solutions for n=4
%e ..0..0..1....1..0..0....0..0..0....0..0..0....0..1..0....1..0..0....0..0..0
%e ..0..0..1....0..1..0....0..0..1....1..0..0....0..0..1....0..0..0....0..0..0
%e ..0..0..0....0..0..0....0..0..0....0..0..0....0..1..0....0..0..0....0..0..1
%e ..0..0..0....0..0..0....0..0..0....0..0..0....0..0..0....0..1..0....0..0..0
%e ..0..0..1....0..1..0....1..1..0....1..0..0....0..0..0....0..0..1....1..0..1
%e ..0..0..1....1..0..0....1..0..0....0..0..0....0..1..0....0..1..0....0..1..0
%Y Cf. A260841
%K nonn
%O 1,1
%A _R. H. Hardin_, Aug 01 2015