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%I #8 Dec 03 2018 08:31:38
%S 897,555,529,570,637,764,903,1117,1470,1843,2410,3329,4304,5795,8196,
%T 10747,14657,20938,27615,37858,54297,71776,98599,141632,187391,257621,
%U 370278,490075,673946,968881,1282512,1763899,2536044,3357139,4617433
%N Number of (n+2) X (2+2) 0..3 arrays with every 3 X 3 subblock row and diagonal sum equal to 0 3 5 6 or 7 and every 3 X 3 column and antidiagonal sum not equal to 0 3 5 6 or 7.
%H R. H. Hardin, <a href="/A252378/b252378.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 4*a(n-3) - 4*a(n-6) + a(n-9) for n>15.
%F Empirical g.f.: x*(897 + 555*x + 529*x^2 - 3018*x^3 - 1583*x^4 - 1352*x^5 + 2211*x^6 + 789*x^7 + 530*x^8 - 386*x^9 - 65*x^10 - 24*x^11 - 26*x^12 - 14*x^13 - 4*x^14) / ((1 - x)*(1 + x + x^2)*(1 - 3*x^3 + x^6)). - _Colin Barker_, Dec 03 2018
%e Some solutions for n=4:
%e ..1..2..0..1....3..0..0..3....0..2..1..3....0..3..0..3....0..0..0..0
%e ..0..2..1..0....2..1..3..3....2..0..1..2....0..3..2..0....0..2..1..0
%e ..0..0..0..0....3..3..1..3....0..0..0..3....1..3..2..1....2..0..1..2
%e ..1..2..0..1....3..0..0..3....0..2..1..3....3..2..0..1....0..0..0..0
%e ..0..2..1..3....3..1..3..3....2..0..1..2....0..3..0..0....0..2..1..0
%e ..0..0..0..0....3..3..1..3....0..0..0..3....1..3..1..1....2..0..3..2
%Y Column 2 of A252384.
%K nonn
%O 1,1
%A _R. H. Hardin_, Dec 17 2014
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