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%I #8 Dec 02 2018 07:14:58
%S 2458,22256,73826,160688,412514,1339010,4297634,13186856,40282992,
%T 123998850,382415504,1178020562,3627007218,11168774306,34396342056,
%U 105928920848,326217328994,1004613387440,3093802840514,9527668767266
%N Number of (n+2) X (5+2) 0..2 arrays with every 3 X 3 subblock row and column sum 2 3 or 4 and every diagonal and antidiagonal sum not 2 3 or 4.
%H R. H. Hardin, <a href="/A252225/b252225.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 3*a(n-1) - a(n-2) + 3*a(n-3) + 3*a(n-4) - a(n-5) - a(n-6) for n>8.
%F Empirical g.f.: 2*x*(1229 + 7441*x + 4758*x^2 - 22954*x^3 - 34933*x^4 - 11816*x^5 + 7145*x^6 + 4720*x^7) / ((1 - x + 2*x^2 - x^3)*(1 - 2*x - 3*x^2 - x^3)). - _Colin Barker_, Dec 02 2018
%e Some solutions for n=4:
%e ..0..2..0..2..0..1..1....1..1..2..1..1..0..2....1..0..2..0..2..0..2
%e ..2..0..2..0..2..0..1....0..2..0..2..0..2..0....1..2..0..2..0..2..0
%e ..0..2..0..2..0..2..1....2..0..2..0..2..0..2....1..0..2..0..2..0..1
%e ..2..0..2..0..2..0..2....0..2..0..2..0..2..0....1..2..0..2..0..2..1
%e ..0..2..0..2..0..2..0....2..0..2..0..2..0..2....1..0..2..0..2..0..2
%e ..1..1..1..0..1..1..1....0..2..0..1..1..1..1....0..2..0..2..0..2..0
%Y Column 5 of A252228.
%K nonn
%O 1,1
%A _R. H. Hardin_, Dec 15 2014
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