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%I #10 Aug 12 2016 06:54:17
%S 0,12,216,2700,54000,1054200,20991600,445365900,9628264800,
%T 212635396512,4790810344320,109495671909624,2534856710978592,
%U 59336480231336880,1402136110916757216,33409975384414912140,801962422581013417152
%N Number of 3 X n arrays containing n copies of 0..3-1 with row sums equal.
%C Row 3 of A268367.
%H R. H. Hardin, <a href="/A268369/b268369.txt">Table of n, a(n) for n = 1..40</a>
%F Conjecture: n^4*(1057*n^2 -3473*n +2902)*a(n) -(n-1) *(14798*n^5 -63420*n^4 +104199*n^3 -81821*n^2 +31698*n -4968)*a(n-1) +(-235711*n^6 +1717323*n^5 -5084885*n^4 +7773081*n^3 -6422772*n^2 +2716308*n -472176)*a(n-2) -96*(6*n -11) *(6*n-13) *(1057*n^2-1359*n+486) *(n-2)^2*a(n-3)=0. - _R. J. Mathar_, Feb 18 2016
%e Some solutions for n=5
%e ..1..1..1..0..2....0..0..2..2..1....1..0..2..1..1....0..1..2..0..2
%e ..0..1..0..2..2....1..1..1..2..0....1..0..2..0..2....0..1..1..1..2
%e ..0..0..2..2..1....0..1..2..0..2....0..0..2..1..2....2..0..0..1..2
%Y Cf. A268367.
%K nonn
%O 1,2
%A _R. H. Hardin_, Feb 03 2016
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