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Number of (n+2)X(5+2) 0..3 arrays with every 3X3 subblock row and column sum not equal to 0 1 3 6 or 7 and every 3X3 diagonal and antidiagonal sum equal to 0 1 3 6 or 7
1

%I #4 Dec 14 2014 16:50:10

%S 5577,4732,9572,15460,29276,57271,114243,225966,451186,898886,1796742,

%T 3567622,7180566,14252982,28550806,57071990,114226230,227100406,

%U 457805238,909211446,1822429366,3645696566,7298665782,14515253302

%N Number of (n+2)X(5+2) 0..3 arrays with every 3X3 subblock row and column sum not equal to 0 1 3 6 or 7 and every 3X3 diagonal and antidiagonal sum equal to 0 1 3 6 or 7

%C Column 5 of A252157

%H R. H. Hardin, <a href="/A252154/b252154.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = -a(n-1) +2*a(n-2) +14*a(n-3) +14*a(n-4) -28*a(n-5) -56*a(n-6) -56*a(n-7) +112*a(n-8) +64*a(n-9) +64*a(n-10) -128*a(n-11) for n>16

%e Some solutions for n=4

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

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

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_, Dec 14 2014