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%I #9 Jun 01 2018 06:01:54
%S 265,1573,9253,54085,317179,1858993,10894297,63850777,374215201,
%T 2193190681,12853833343,75333557377,441513844561,2587618272973,
%U 15165477047269,88881616706701,520916142332515,3052978074328417
%N Number of (n+2) X 3 binary arrays with no more than two of any consecutive three bits set in any row or column.
%C Column 1 of A202471.
%H R. H. Hardin, <a href="/A202464/b202464.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 4*a(n-1) +8*a(n-2) +18*a(n-3) -6*a(n-4) +2*a(n-5) -a(n-6).
%F Empirical g.f.: x*(265 + 513*x + 841*x^2 - 281*x^3 + 91*x^4 - 49*x^5) / (1 - 4*x - 8*x^2 - 18*x^3 + 6*x^4 - 2*x^5 + x^6). - _Colin Barker_, Jun 01 2018
%e Some solutions for n=4:
%e ..0..1..0....1..0..0....1..0..0....0..0..0....1..0..1....0..0..0....0..1..1
%e ..0..0..1....1..0..1....0..1..0....1..0..1....0..1..0....0..1..0....0..1..1
%e ..0..1..0....0..1..0....0..1..0....1..0..0....0..0..0....1..1..0....1..0..0
%e ..0..0..0....0..0..0....1..0..0....0..1..1....0..0..0....0..0..0....0..1..0
%e ..0..1..1....0..0..1....0..1..0....0..1..1....0..1..1....0..0..0....1..1..0
%e ..1..0..1....0..1..1....0..0..0....0..0..0....0..1..0....1..0..0....1..0..1
%Y Cf. A202471.
%K nonn
%O 1,1
%A _R. H. Hardin_, Dec 19 2011
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