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%I #8 Dec 30 2018 06:35:13
%S 33,52,106,206,402,790,1546,3026,5928,11610,22736,44526,87200,170774,
%T 334446,654980,1282716,2512082,4919682,9634740,18868742,36952682,
%U 72368406,141726816,277558826,543573226,1064537776,2084798554,4082884696
%N Number of (n+2) X (2+2) 0..1 arrays with each 3 X 3 subblock having clockwise perimeter pattern 00010001 00010101 or 01010101.
%H R. H. Hardin, <a href="/A261107/b261107.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = a(n-1) +2*a(n-3) +2*a(n-4) +2*a(n-5) +a(n-6) for n>7.
%F Empirical g.f.: x*(33 + 19*x + 54*x^2 + 34*x^3 + 26*x^4 + 6*x^5 - 5*x^6) / (1 - x - 2*x^3 - 2*x^4 - 2*x^5 - x^6). - _Colin Barker_, Dec 30 2018
%e Some solutions for n=4:
%e ..1..0..1..0....1..0..1..0....0..1..0..1....0..1..0..0....1..0..1..0
%e ..0..1..0..0....0..1..0..0....1..0..0..0....1..0..1..0....0..1..0..1
%e ..1..0..1..0....1..0..1..0....0..1..0..1....0..0..0..1....1..0..1..0
%e ..0..1..0..1....0..1..0..1....1..0..1..0....1..0..1..0....0..0..0..1
%e ..0..0..1..0....0..0..1..0....0..1..0..1....0..1..0..1....1..0..1..0
%e ..0..1..0..1....0..1..0..0....1..0..0..0....1..0..1..0....0..1..0..1
%Y Column 2 of A261113.
%K nonn
%O 1,1
%A _R. H. Hardin_, Aug 08 2015
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