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A252311 Number of (6+2)X(n+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

%S 3681,3476,5416,7489,14515,24076,34279,70643,120328,173799,386803,

%T 679072,998407,2392371,4310288,6431079,16347187,30013936,45246631,

%U 119642163,222278576,337209639,912658483,1706977072,2598711847,7123476531

%N Number of (6+2)X(n+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 Row 6 of A252305

%H R. H. Hardin, <a href="/A252311/b252311.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 15*a(n-3) -70*a(n-6) +120*a(n-9) -64*a(n-12) for n>21

%e Some solutions for n=4

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

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

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

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

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_, Dec 16 2014

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Last modified August 15 14:39 EDT 2022. Contains 356145 sequences. (Running on oeis4.)