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

%I #4 Dec 15 2014 07:49:12

%S 585,470,669,1313,3201,8526,23265,63626,174878,481751,1326853,3654591,

%T 10068350,27738291,76416644,210524622,579990251,1597852801,4402028111,

%U 12127445456,33410714513,92045405856,253582052916,698610194687

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

%C Column 2 of A252201

%H R. H. Hardin, <a href="/A252195/b252195.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = a(n-1) +a(n-2) +7*a(n-3) +7*a(n-4) +7*a(n-5) +4*a(n-6) -2*a(n-7) -4*a(n-8) -9*a(n-9) -8*a(n-10) -7*a(n-11) -3*a(n-12) +a(n-13) +3*a(n-14) +2*a(n-15) +a(n-16) for n>21

%e Some solutions for n=4

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

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

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_, Dec 15 2014