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%I #9 Apr 02 2018 13:02:06
%S 41209,126223,451801,1803007,7794409,35840623,173139001,870960607,
%T 4532521609,24280115023,133365034201,748813846207,4287144320809,
%U 24977332069423,147837168257401,887722723579807,5401539971032009
%N Number of (n+1) X 5 0..6 arrays with every 2 X 2 subblock summing to 12.
%C Column 4 of A183672.
%H R. H. Hardin, <a href="/A183667/b183667.txt">Table of n, a(n) for n = 1..90</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*(41209 - 1027629*x + 10186855*x^2 - 50973255*x^3 + 134336776*x^4 - 174117636*x^5 + 84707280*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 5:
%e ..0..2..5..4..3....1..4..2..6..0....3..4..2..2..3....1..4..4..2..1
%e ..6..4..1..2..3....1..6..0..4..2....2..3..3..5..2....5..2..2..4..5
%e ..1..1..6..3..4....4..1..5..3..3....3..4..2..2..3....2..3..5..1..2
%Y Cf. A183672.
%K nonn
%O 1,1
%A _R. H. Hardin_, Jan 06 2011
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