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%I #8 Dec 02 2018 07:15:15
%S 228,368,812,1442,2458,4738,9922,20070,38774,75106,148914,296946,
%T 586790,1153474,2273494,4495766,8887778,17542298,34612226,68336662,
%U 134968250,266516414,526161790,1038785394,2051072242,4049909170,7996310710
%N Number of (n+2) X (1+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="/A252221/b252221.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 2*a(n-1) - a(n-2) + a(n-3) + 3*a(n-4) - 2*a(n-5) - 2*a(n-7) for n>10.
%F Empirical g.f.: 2*x*(114 - 44*x + 152*x^2 - 21*x^3 - 333*x^4 - 98*x^5 - 119*x^6 + 130*x^7 + 32*x^8 + 16*x^9) / ((1 - x)*(1 - x - x^3 - 4*x^4 - 2*x^5 - 2*x^6)). - _Colin Barker_, Dec 02 2018
%e Some solutions for n=4:
%e ..1..1..1....1..0..2....0..1..1....0..1..1....1..2..1....1..0..2....1..0..1
%e ..0..2..1....1..2..0....2..0..2....2..0..1....0..2..1....1..2..0....2..0..1
%e ..2..0..2....1..0..2....0..2..0....0..2..1....2..0..2....2..0..2....0..2..0
%e ..0..2..0....1..2..0....2..0..2....2..0..2....0..2..0....0..2..0....2..0..1
%e ..1..0..1....1..0..2....1..2..1....0..2..0....1..0..1....2..0..1....0..2..1
%e ..1..0..1....1..2..0....1..1..1....1..1..1....1..1..1....0..1..1....2..0..1
%Y Column 1 of A252228.
%K nonn
%O 1,1
%A _R. H. Hardin_, Dec 15 2014
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