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

%I #4 Dec 17 2014 09:58:41

%S 319,688,1515,2555,7425,18377,32710,97923,245711,440341,1327285,

%T 3343809,6005069,18174197,45900357,82546379,250597823,634117095,

%U 1141608889,3474085061,8803935237,15862997397,48363153977,122700674105,221224063343

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

%C Row 3 of A252407

%H R. H. Hardin, <a href="/A252410/b252410.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 26*a(n-3) -179*a(n-6) +122*a(n-9) +562*a(n-12) -680*a(n-15) -425*a(n-18) +768*a(n-21) +19*a(n-24) -236*a(n-27) +24*a(n-30) for n>37

%e Some solutions for n=4

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

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_, Dec 17 2014