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%I #7 Dec 01 2018 07:58:01
%S 1929,1424,724,584,624,788,1180,1668,2472,3888,5640,8592,13920,20496,
%T 31776,52416,77856,121920,203136,303168,477312,799488,1196160,1888512,
%U 3171840,4751616,7512576,12635136,18940416,29967360,50436096,75629568
%N Number of (n+2) X (2+2) 0..3 arrays with every 3 X 3 subblock row and column sum equal to 0 2 3 6 or 7 and every 3 X 3 diagonal and antidiagonal sum not equal to 0 2 3 6 or 7.
%H R. H. Hardin, <a href="/A252108/b252108.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 6*a(n-3) - 8*a(n-6) for n>13.
%F Empirical g.f.: x*(1929 + 1424*x + 724*x^2 - 10990*x^3 - 7920*x^4 - 3556*x^5 + 13108*x^6 + 9316*x^7 + 3536*x^8 + 1480*x^9 + 624*x^10 + 64*x^11 + 32*x^12) / ((1 - 2*x^3)*(1 - 4*x^3)). - _Colin Barker_, Dec 01 2018
%e Some solutions for n=4:
%e ..3..3..1..3....0..2..1..0....0..1..1..0....3..1..2..0....1..3..3..1
%e ..2..2..3..2....3..3..0..0....3..0..0..2....3..2..1..0....3..2..2..3
%e ..2..2..3..2....0..1..2..3....0..1..1..0....0..3..0..3....3..2..2..3
%e ..3..3..1..3....3..2..1..0....0..1..1..0....0..1..2..3....1..3..3..0
%e ..2..2..3..1....0..0..3..3....2..0..0..3....3..3..0..0....3..2..2..3
%e ..1..2..3..2....0..1..2..0....0..1..1..0....3..2..1..0....3..2..2..3
%Y Column 2 of A252114.
%K nonn
%O 1,1
%A _R. H. Hardin_, Dec 14 2014
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