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%I #8 Mar 20 2018 06:51:48
%S 1752,790,1636,2660,6072,9836,17774,38612,70970,132530,284490,536930,
%T 1021634,2178338,4172162,8018690,17036418,32884226,63532034,134730242,
%U 261101570,505786370,1071597570,2080923650,4036411394,8547803138
%N Number of (n+2) X (6+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.
%C Column 6 of A251894.
%H R. H. Hardin, <a href="/A251892/b251892.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = a(n-1) + 12*a(n-3) - 12*a(n-4) - 32*a(n-6) + 32*a(n-7) for n>12.
%F Empirical g.f.: 2*x*(876 - 481*x + 423*x^2 - 10000*x^3 + 7478*x^4 - 3194*x^5 + 25857*x^6 - 25445*x^7 + 7131*x^8 - 464*x^9 + 5544*x^10 - 7704*x^11) / ((1 - x)*(1 - 2*x)*(1 + 2*x + 4*x^2)*(1 - 4*x^3)). - _Colin Barker_, Mar 20 2018
%e Some solutions for n=4:
%e ..2..3..3..2..3..3..2..0....0..2..2..0..2..2..1..2....1..3..1..1..2..1..1..2
%e ..1..2..2..1..2..2..0..2....2..3..3..2..3..3..2..3....0..1..0..0..1..0..0..1
%e ..2..3..3..2..3..3..2..3....2..3..3..2..3..3..2..3....0..1..0..0..1..0..0..1
%e ..2..3..3..2..3..3..2..3....1..2..2..1..2..2..1..2....1..2..1..1..2..1..1..3
%e ..0..2..2..0..2..2..0..2....2..3..3..2..3..3..2..3....0..1..0..0..1..0..0..1
%e ..2..3..3..2..3..3..2..3....2..3..3..2..3..3..2..3....0..1..0..0..1..0..0..1
%Y Cf. A251894.
%K nonn
%O 1,1
%A _R. H. Hardin_, Dec 10 2014
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