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%I #7 Mar 20 2018 10:16:49
%S 134,156,431,1183,3163,8684,24031,66098,181896,501355,1381325,3804929,
%T 10482568,28879979,79562524,219191134,603866443,1663632329,4583248173,
%U 12626699534,34786145503,95834674276,264021357876,727370136485
%N Number of (n+2) X (2+2) 0..3 arrays with every 3 X 3 subblock row, column, diagonal and antidiagonal sum not equal to 0 3 4 6 or 7.
%C Column 2 of A252139.
%H R. H. Hardin, <a href="/A252133/b252133.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 2*a(n-1) + a(n-2) + 4*a(n-3) - a(n-4) - 4*a(n-5) - 3*a(n-6) + a(n-8) + a(n-9) for n>11.
%F Empirical g.f.: x*(134 - 112*x - 15*x^2 - 371*x^3 - 124*x^4 + 143*x^5 + 225*x^6 + 75*x^7 - 13*x^8 - 64*x^9 - 4*x^10) / ((1 - x)*(1 - x - 2*x^2 - 6*x^3 - 5*x^4 - x^5 + 2*x^6 + 2*x^7 + x^8)). - _Colin Barker_, Mar 20 2018
%e Some solutions for n=4:
%e ..3..3..3..3....3..3..2..3....3..3..3..2....3..3..3..2....3..3..3..3
%e ..3..3..3..3....3..3..3..3....3..3..3..3....3..3..3..3....3..2..3..3
%e ..3..3..3..2....3..3..3..3....2..3..3..3....3..3..2..3....3..3..3..2
%e ..3..3..3..3....3..2..3..3....3..3..3..3....2..3..3..3....3..3..3..3
%e ..2..3..3..3....3..3..3..2....3..3..3..2....3..3..3..3....3..3..3..3
%e ..3..3..2..3....3..3..2..0....3..3..3..3....3..3..3..2....3..2..3..3
%Y Cf. A252139.
%K nonn
%O 1,1
%A _R. H. Hardin_, Dec 14 2014
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