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%I #9 Feb 27 2018 08:33:23
%S 35,195,1028,5529,29593,158648,850155,4556371,24418812,130868377,
%T 701364193,3758831480,20144755955,107962068819,578602594196,
%U 3100912827657,16618764665065,89065173542888,477328206813915
%N Number of (n+1) X 3 binary arrays with no 2 X 2 subblock containing fewer than two 1s.
%C Column 2 of A184207.
%H R. H. Hardin, <a href="/A184200/b184200.txt">Table of n, a(n) for n = 1..200</a>
%F Empirical: a(n) = 5*a(n-1) + 4*a(n-2) - 11*a(n-3) - a(n-4) + 2*a(n-5).
%F Empirical g.f.: x*(35 + 20*x - 87*x^2 - 6*x^3 + 16*x^4) / (1 - 5*x - 4*x^2 + 11*x^3 + x^4 - 2*x^5). - _Colin Barker_, Feb 27 2018
%e Some solutions for 5 X 3:
%e ..0..1..1....1..1..0....1..1..0....1..1..1....0..1..0....0..0..1....1..1..0
%e ..1..0..0....1..0..1....1..0..1....1..1..0....1..1..0....1..1..0....1..1..1
%e ..0..1..1....0..1..1....1..1..0....1..0..1....1..1..1....0..1..1....1..1..0
%e ..1..1..1....0..1..0....1..1..0....0..1..0....0..1..0....1..0..1....0..1..1
%e ..0..1..1....0..1..1....1..0..1....0..1..0....1..1..1....1..0..1....1..0..0
%Y Cf. A184207.
%K nonn
%O 1,1
%A _R. H. Hardin_, Jan 10 2011
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