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%I #8 Dec 30 2018 09:10:31
%S 36,41,91,166,321,586,1123,2082,3938,7358,13863,25971,48833,91602,
%T 172099,323001,606629,1138805,2138465,4014874,7538696,14154181,
%U 26576436,49899170,93691463,175913869,330296900,620163290,1164419552,2186309750
%N Number of (n+2) X (1+2) 0..1 arrays with each 3 X 3 subblock having clockwise perimeter pattern 00010101 00100101 or 01010101.
%H R. H. Hardin, <a href="/A261258/b261258.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = a(n-1) + a(n-2) + 2*a(n-4) + a(n-6) for n>7.
%F Empirical g.f.: x*(36 + 5*x + 14*x^2 + 34*x^3 - 8*x^4 + 17*x^5 - 2*x^6) / (1 - x - x^2 - 2*x^4 - x^6). - _Colin Barker_, Dec 30 2018
%e Some solutions for n=4:
%e ..1..0..0....0..1..0....0..1..0....1..0..1....0..1..0....1..0..0....1..0..0
%e ..0..0..0....1..0..1....1..0..1....0..1..0....1..0..1....0..0..1....0..1..0
%e ..1..0..1....0..0..0....0..1..0....0..1..0....0..0..0....1..0..0....1..0..1
%e ..0..1..0....1..0..1....0..1..0....1..0..1....1..0..1....0..0..1....0..1..0
%e ..1..0..1....0..1..0....1..0..1....0..1..0....0..1..0....1..0..0....0..0..1
%e ..0..0..0....1..0..0....0..0..0....1..0..1....0..0..1....0..0..1....0..1..0
%Y Column 1 of A261265.
%K nonn
%O 1,1
%A _R. H. Hardin_, Aug 13 2015
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