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A187529 Number of 3X3 0..n arrays with each 2X2 subblock determinant nonzero and the array of 2X2 subblock determinants symmetric under 90 degree rotation.

%I A187529 #7 Jul 22 2025 10:48:41
%S A187529 0,8,74,280,784,1970,3580,6946,11726,19100,27672,44092,58988,83340,
%T A187529 116344,156470,193434,262028,316330,414216,517530,629058,735548,
%U A187529 935702,1100836,1299196,1530340,1835766,2068728,2511536,2794280,3249058,3723336
%N A187529 Number of 3X3 0..n arrays with each 2X2 subblock determinant nonzero and the array of 2X2 subblock determinants symmetric under 90 degree rotation.
%C A187529 Row 2 of A187528
%H A187529 R. H. Hardin, <a href="/A187529/b187529.txt">Table of n, a(n) for n = 1..36</a>
%e A187529 Some solutions for 3X3
%e A187529 ..2..3..0....0..3..2....0..1..2....3..2..3....3..3..0....1..1..0....1..2..3
%e A187529 ..1..3..1....1..3..1....2..2..2....1..1..2....1..2..1....1..3..2....1..1..1
%e A187529 ..0..3..2....2..3..0....3..2..1....0..1..3....0..3..3....0..2..2....3..2..1
%K A187529 nonn
%O A187529 1,2
%A A187529 _R. H. Hardin_ Mar 10 2011