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

%I #4 Dec 16 2014 15:20:39

%S 1675,1370,1677,2151,3669,5416,7492,13386,20379,28688,51938,79730,

%T 112972,205370,316178,449108,817514,1260050,1791652,3262922,5031698,

%U 7157828,13038218,20110610,28614532,52126730,80410898,114425348,208455434

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

%C Column 3 of A252305

%H R. H. Hardin, <a href="/A252300/b252300.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 7*a(n-3) -14*a(n-6) +8*a(n-9) for n>18

%e Some solutions for n=4

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

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

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_, Dec 16 2014