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%I #9 Apr 02 2018 13:02:03
%S 6951,24745,100935,451801,2163831,10914505,57370215,311907001,
%T 1744391511,9994250665,58473101895,348467631001,2110957895991,
%U 12976935385225,80838681063975,509665597255801,3248622235733271,20914068068750185
%N Number of (n+1) X 4 0..6 arrays with every 2 X 2 subblock summing to 12.
%C Column 3 of A183672.
%H R. H. Hardin, <a href="/A183666/b183666.txt">Table of n, a(n) for n = 1..200</a>
%F Empirical: a(n) = 28*a(n-1) - 322*a(n-2) + 1960*a(n-3) - 6769*a(n-4) + 13132*a(n-5) - 13068*a(n-6) + 5040*a(n-7).
%F Empirical g.f.: x*(6951 - 169883*x + 1646297*x^2 - 8030449*x^3 + 20565592*x^4 - 25807068*x^5 + 12101040*x^6) / ((1 - x)*(1 - 2*x)*(1 - 3*x)*(1 - 4*x)*(1 - 5*x)*(1 - 6*x)*(1 - 7*x)). - _Colin Barker_, Apr 02 2018
%e Some solutions for 3 X 4:
%e ..0..6..2..2....1..4..1..5....6..5..3..3....4..1..5..0....5..4..3..3
%e ..5..1..3..5....1..6..1..5....1..0..4..2....6..1..5..2....1..2..3..3
%e ..1..5..3..1....1..4..1..5....6..5..3..3....1..4..2..3....3..6..1..5
%Y Cf. A183672.
%K nonn
%O 1,1
%A _R. H. Hardin_, Jan 06 2011
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