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%I #8 Apr 09 2018 13:00:57
%S 171,309,579,1233,2691,6417,15555,40041,104211,282609,771699,2167353,
%T 6111171,17563617,50584035,147570921,430968051,1269505809,3741492819,
%U 11090690073,32883337251,97873303617,291340216515,869463485001
%N Number of (n+1) X 3 0..2 arrays with all 2 X 2 subblock sums the same.
%C Column 2 of A184003.
%H R. H. Hardin, <a href="/A183996/b183996.txt">Table of n, a(n) for n = 1..200</a>
%F Empirical: a(n) = 6*a(n-1) - 60*a(n-3) + 85*a(n-4) + 150*a(n-5) - 360*a(n-6) + 396*a(n-8) - 216*a(n-9).
%F Empirical g.f.: 3*x*(57 - 239*x - 425*x^2 + 2673*x^3 - 234*x^4 - 8968*x^5 + 5676*x^6 + 9252*x^7 - 7992*x^8) / ((1 - x)*(1 - 2*x)*(1 - 3*x)*(1 - 2*x^2)*(1 - 3*x^2)*(1 - 6*x^2)). - _Colin Barker_, Apr 09 2018
%e Some solutions for 4 X 3:
%e ..1..2..1....0..2..0....2..0..2....0..2..0....1..2..2....0..2..1....2..0..1
%e ..0..1..0....1..0..1....2..1..2....0..2..0....1..2..0....1..2..0....1..2..2
%e ..1..2..1....1..1..1....1..1..1....0..2..0....1..2..2....1..1..2....2..0..1
%e ..1..0..1....1..0..1....1..2..1....0..2..0....1..2..0....2..1..1....1..2..2
%Y Cf. A184003.
%K nonn
%O 1,1
%A _R. H. Hardin_, Jan 08 2011
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