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Number of (n+2)X(6+2) 0..3 arrays with every 3X3 subblock row and column sum not equal to 1 3 4 6 or 7 and every 3X3 diagonal and antidiagonal sum equal to 1 3 4 6 or 7
1

%I #4 Dec 15 2014 19:25:53

%S 34364,932024,22430004,84935088,2778727776,78534150416,267361717440,

%T 9906342078848,303070072292928,959873651073792,38221223204832768,

%U 1212189579390626048,3685070395096108032,152413070389286672384

%N Number of (n+2)X(6+2) 0..3 arrays with every 3X3 subblock row and column sum not equal to 1 3 4 6 or 7 and every 3X3 diagonal and antidiagonal sum equal to 1 3 4 6 or 7

%C Column 6 of A252243

%H R. H. Hardin, <a href="/A252241/b252241.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 7180*a(n-3) -14766112*a(n-6) +8766324736*a(n-9) -103548977152*a(n-12) +274877906944*a(n-15) for n>16

%e Some solutions for n=1

%e ..2..3..3..2..0..0..2..3....0..2..0..3..2..3..3..2....0..0..2..3..3..2..3..3

%e ..2..0..0..2..3..0..2..0....1..3..1..1..0..1..1..0....2..2..1..2..2..1..2..2

%e ..1..2..2..1..2..2..1..2....1..3..1..1..0..1..1..3....3..3..2..0..0..2..0..0

%K nonn

%O 1,1

%A _R. H. Hardin_, Dec 15 2014