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%I #13 Apr 03 2018 09:14:57
%S 13448,54496,252920,1287136,7003928,40112416,239241080,1474919776,
%T 9347624408,60651538336,401609136440,2707018165216,18536292500888,
%U 128729069556256,905422420235000,6442255273423456,46323252106113368
%N Number of (n+1) X 4 0..7 arrays with every 2 X 2 subblock summing to 14.
%C Column 3 of A183680.
%H R. H. Hardin, <a href="/A183676/b183676.txt">Table of n, a(n) for n = 1..150</a>
%F Empirical: a(n) = 36*a(n-1) - 546*a(n-2) + 4536*a(n-3) - 22449*a(n-4) + 67284*a(n-5) - 118124*a(n-6) + 109584*a(n-7) - 40320*a(n-8).
%F Empirical g.f.: 8*x*(1681 - 53704*x + 704209*x^2 - 4882912*x^3 + 19182706*x^4 - 42244048*x^5 + 47564208*x^6 - 20643840*x^7) / ((1 - x)*(1 - 2*x)*(1 - 3*x)*(1 - 4*x)*(1 - 5*x)*(1 - 6*x)*(1 - 7*x)*(1 - 8*x)). - _Colin Barker_, Apr 03 2018
%e Some solutions for 3 X 4:
%e ..3..3..3..0....6..0..1..4....1..2..0..6....5..3..4..3....4..7..3..6
%e ..6..2..6..5....1..7..6..3....4..7..5..3....6..0..7..0....0..3..1..4
%e ..3..3..3..0....6..0..1..4....3..0..2..4....4..4..3..4....6..5..5..4
%Y Cf. A183680.
%K nonn
%O 1,1
%A _R. H. Hardin_, Jan 06 2011
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