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%I #10 Mar 31 2018 14:29:23
%S 21016,31060,53512,105604,231736,551380,1398952,3743524,10479256,
%T 30483700,91664392,283832644,902755576,2945024020,9845481832,
%U 33704772964,118040932696,422335788340,1540872323272,5720102724484,21554302962616
%N Number of (n+1) X 7 0..3 arrays with every 2 X 2 subblock summing to 6.
%C Column 6 of A183642.
%H R. H. Hardin, <a href="/A183639/b183639.txt">Table of n, a(n) for n = 1..77</a>
%F Empirical: a(n) = 10*a(n-1) - 35*a(n-2) + 50*a(n-3) - 24*a(n-4).
%F Conjectures from _Colin Barker_, Mar 31 2018: (Start)
%F G.f.: 4*x*(5254 - 44775*x + 119618*x^2 - 98304*x^3) / ((1 - x)*(1 - 2*x)*(1 - 3*x)*(1 - 4*x)).
%F a(n) = 12138 + 483*2^(3+n) + 14*3^(3+n) + 4^(1+n).
%F (End)
%e Some solutions for 3 X 7:
%e 0 0 1 3 1 2 3 3 2 3 3 0 0 1 3 0 1 0 3 1 3
%e 3 3 2 0 2 1 0 0 1 0 0 3 3 2 1 2 3 2 1 1 1
%e 0 0 1 3 1 2 3 3 2 3 3 0 0 1 2 1 0 1 2 2 2
%Y Cf. A183642.
%K nonn
%O 1,1
%A _R. H. Hardin_, Jan 06 2011
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