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%I #8 Nov 30 2018 15:21:45
%S 1280,602,556,778,1260,1636,2478,3940,5958,9178,14534,22666,35250,
%T 55690,88338,138082,217874,348706,546498,861730,1385538,2174338,
%U 3427394,5523586,8674050,13670530,22057218,34649602,54604034,88154626,138505218
%N Number of (n+2) X (3+2) 0..3 arrays with every 3 X 3 subblock row and column sum not 2 3 6 or 7 and every diagonal and antidiagonal sum 2 3 6 or 7.
%H R. H. Hardin, <a href="/A251889/b251889.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = a(n-1) + 6*a(n-3) - 6*a(n-4) - 8*a(n-6) + 8*a(n-7) for n>12.
%F Empirical g.f.: 2*x*(640 - 339*x - 23*x^2 - 3729*x^3 + 2275*x^4 + 326*x^5 + 4875*x^6 - 3427*x^7 - 303*x^8 - 28*x^9 + 220*x^10 - 484*x^11) / ((1 - x)*(1 - 2*x^3)*(1 - 4*x^3)). - _Colin Barker_, Nov 30 2018
%e Some solutions for n=4:
%e ..0..0..1..0..0....2..3..0..1..0....3..3..2..3..0....2..1..1..2..1
%e ..0..0..1..0..0....1..0..0..1..0....3..3..2..3..3....1..0..0..1..0
%e ..1..1..3..1..1....2..1..1..3..1....2..2..0..2..2....1..0..0..1..0
%e ..0..0..1..0..0....1..0..0..1..0....3..3..2..3..3....2..1..1..3..1
%e ..3..0..1..0..3....1..0..0..1..0....3..3..2..3..0....1..0..0..1..3
%e ..1..1..2..1..1....3..1..1..2..1....2..2..0..2..2....1..0..0..1..0
%Y Column 3 of A251894.
%K nonn
%O 1,1
%A _R. H. Hardin_, Dec 10 2014