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%I #7 Dec 03 2018 18:32:11
%S 806,791,475,660,1093,1471,2176,3809,6101,9098,16197,27215,40668,
%T 72707,123525,184674,330481,562847,841564,1506331,2566837,3838002,
%U 6870033,11708143,17506412,31336843,53406693,79855586,142943489,243616831
%N Number of (n+2) X (1+2) 0..3 arrays with every 3 X 3 subblock row and column sum not equal to 0 2 4 6 or 7 and every 3 X 3 diagonal and antidiagonal sum equal to 0 2 4 6 or 7.
%H R. H. Hardin, <a href="/A252516/b252516.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 6*a(n-3) - 7*a(n-6) + 2*a(n-9) for n>14.
%F Empirical g.f.: x*(806 + 791*x + 475*x^2 - 4176*x^3 - 3653*x^4 - 1379*x^5 + 3858*x^6 + 2788*x^7 + 600*x^8 - 950*x^9 - 588*x^10 - 44*x^11 - 8*x^12 + 2*x^13) / ((1 - x)*(1 + x + x^2)*(1 - 5*x^3 + 2*x^6)). - _Colin Barker_, Dec 03 2018
%e Some solutions for n=4:
%e ..2..1..2....1..1..1....0..2..3....3..2..0....0..3..2....0..0..3....1..1..1
%e ..3..2..0....2..1..0....2..1..2....0..2..3....3..3..2....1..2..2....0..1..2
%e ..3..2..3....2..1..2....3..2..3....2..1..2....2..2..1....2..3..0....2..1..2
%e ..2..1..2....1..3..1....3..2..3....3..2..3....3..3..2....2..3..3....1..3..1
%e ..0..2..3....2..1..2....2..1..2....3..2..0....0..3..2....1..2..2....2..1..2
%e ..3..2..3....2..1..2....0..0..3....2..1..2....2..2..1....2..0..3....2..1..0
%Y Column 1 of A252523.
%K nonn
%O 1,1
%A _R. H. Hardin_, Dec 18 2014