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Number of (n+2)X(4+2) 0..3 arrays with every 3X3 subblock row, column, diagonal and antidiagonal sum not equal to 0 2 5 6 or 7
1

%I #4 Dec 15 2014 09:52:39

%S 3147,2836,10486,44776,188866,801122,3410786,14539238,61939226,

%T 263654432,1122558798,4780929468,20360099382,86698049968,369189620578,

%U 1572170465502,6694947958402,28509673198294,121405330624876

%N Number of (n+2)X(4+2) 0..3 arrays with every 3X3 subblock row, column, diagonal and antidiagonal sum not equal to 0 2 5 6 or 7

%C Column 4 of A252219

%H R. H. Hardin, <a href="/A252215/b252215.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = a(n-1) +6*a(n-2) +21*a(n-3) +53*a(n-4) +32*a(n-5) -61*a(n-6) -245*a(n-7) -323*a(n-8) +337*a(n-9) +944*a(n-10) +125*a(n-11) -1087*a(n-12) -852*a(n-13) +494*a(n-14) +889*a(n-15) +81*a(n-16) -280*a(n-17) -101*a(n-18) -17*a(n-19) -51*a(n-20) -9*a(n-21) +28*a(n-22) +a(n-23) +12*a(n-24) +7*a(n-25) -4*a(n-26) for n>29

%e Some solutions for n=4

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

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

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_, Dec 15 2014