%I #11 Apr 02 2018 13:01:57
%S 231,1225,6951,41209,251991,1577065,10049991,64979929,425156151,
%T 2809324105,18717758631,125589227449,847704901911,5751142882345,
%U 39189002324871,268044330063769,1839301120097271,12656313719435785
%N Number of (n+1) X 2 0..6 arrays with every 2 X 2 subblock summing to 12.
%C Column 1 of A183672.
%H R. H. Hardin, <a href="/A183664/b183664.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*(231 - 5243*x + 47033*x^2 - 211729*x^3 + 499000*x^4 - 574812*x^5 + 246960*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 2:
%e ..4..4....5..3....1..5....3..3....4..6....6..0....4..3....4..2....2..3....3..1
%e ..4..0....4..0....3..3....1..5....1..1....2..4....2..3....2..4....6..1....6..2
%e ..6..2....5..3....3..3....6..0....4..6....5..1....4..3....3..3....1..4....3..1
%Y Cf. A183672.
%K nonn
%O 1,1
%A _R. H. Hardin_, Jan 06 2011