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%I #8 Jul 13 2018 05:48:04
%S 8,41,227,1331,8123,50987,326123,2111531,13777067,90322091,593895083,
%T 3912075947,25797704363,170233203371,1123784731307,7420419975851,
%U 49004773878443,323658783566507,2137765638482603,14120404331440811
%N Number of (n+1) X 2 0..3 arrays with every 2 X 2 subblock having one or two distinct values, and new values 0..3 introduced in row major order.
%C Column 1 of A209848.
%H R. H. Hardin, <a href="/A209841/b209841.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 11*a(n-1) - 30*a(n-2) + 4*a(n-3) + 16*a(n-4).
%F Empirical g.f.: x*(8 - 47*x + 16*x^2 + 32*x^3) / ((1 - x)*(1 - 4*x)*(1 - 6*x - 4*x^2)). - _Colin Barker_, Jul 13 2018
%e Some solutions for n=4:
%e ..0..0....0..1....0..1....0..0....0..0....0..0....0..0....0..1....0..1....0..1
%e ..0..0....0..0....0..1....1..0....0..0....0..0....1..0....0..0....0..0....0..0
%e ..1..0....0..1....0..0....0..1....0..0....0..0....0..1....0..0....0..1....2..2
%e ..0..0....0..1....0..0....1..0....1..0....0..0....1..0....1..0....0..0....0..0
%e ..2..0....0..0....0..0....0..1....1..0....0..0....0..0....0..0....2..2....2..2
%Y Cf. A209848.
%K nonn
%O 1,1
%A _R. H. Hardin_, Mar 14 2012
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