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Number of 3X3 0..n arrays with each 2X2 subblock off diagonal and antidiagonal nonsingular and the array of 2X2 subblock determinants antisymmetric about the diagonal and antidiagonal
1

%I #5 Mar 31 2012 12:36:09

%S 128,1489,8272,31461,93476,235773,524284,1062857,1999212,3541677,

%T 5967404,9648841,15048584,22766353,33534080,48248321,67983232,

%U 94042589,127929948,171449249,226655576,295941137,382036240,488090685,617595596,774557293

%N Number of 3X3 0..n arrays with each 2X2 subblock off diagonal and antidiagonal nonsingular and the array of 2X2 subblock determinants antisymmetric about the diagonal and antidiagonal

%C Row 2 of A187705

%H R. H. Hardin, <a href="/A187706/b187706.txt">Table of n, a(n) for n = 1..33</a>

%e Some n=3 solutions for 3X3

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_ Mar 12 2011