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%I #8 Mar 20 2018 06:51:55
%S 1280,530,778,1316,1958,2660,4490,7250,10634,17954,28994,42530,71810,
%T 115970,170114,287234,463874,680450,1148930,1855490,2721794,4595714,
%U 7421954,10887170,18382850,29687810,43548674,73531394,118751234
%N Number of (n+2) X (4+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 4 of A251894.
%H R. H. Hardin, <a href="/A251890/b251890.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = a(n-1) + 4*a(n-3) - 4*a(n-4) for n>9.
%F Empirical g.f.: 2*x*(640 - 375*x + 124*x^2 - 2291*x^3 + 1821*x^4 - 145*x^5 - 161*x^6 + 96*x^7 + 288*x^8) / ((1 - x)*(1 - 4*x^3)). - _Colin Barker_, Mar 20 2018
%e Some solutions for n=4:
%e ..1..1..2..1..1..2....2..3..3..2..0..3....0..1..0..0..1..3....0..0..1..0..0..1
%e ..3..0..1..0..0..1....0..2..2..0..2..2....1..3..1..1..3..1....1..1..3..1..1..2
%e ..0..0..1..0..0..1....2..3..3..2..3..3....0..1..0..0..1..0....0..0..1..0..0..1
%e ..1..1..3..1..1..2....2..3..3..2..3..3....0..1..0..0..1..0....0..0..1..0..0..1
%e ..0..0..1..0..0..1....0..2..2..0..2..2....1..3..1..1..3..1....1..1..2..1..1..2
%e ..3..0..1..0..0..1....2..3..3..2..0..3....3..1..0..0..1..0....0..0..1..0..0..1
%Y Cf. A251894.
%K nonn
%O 1,1
%A _R. H. Hardin_, Dec 10 2014