A187671
Number of 3X3 0..n arrays with each 2X2 subblock nonsingular and the array of 2X2 subblock determinants symmetric about the diagonal and antidiagonal.
Original entry on oeis.org
24, 550, 4044, 17716, 56080, 150166, 336776, 702408, 1330728, 2385910, 3973400, 6550700, 10068336, 15247986, 22545648, 32579360, 45246528, 62983046, 84524916, 113900920, 150370548, 195521534, 249456396, 321513812, 404142192, 504603526
Offset: 1
Some n=3 solutions for 3X3
..3..3..3....2..1..3....0..1..0....2..1..1....1..0..3....3..0..2....2..3..1
..0..1..0....2..0..2....2..1..2....2..2..0....0..3..2....0..1..2....1..0..1
..3..0..3....0..1..0....2..2..2....2..1..1....3..3..3....2..0..3....2..3..2
A187668
Number of (n+1)X(n+1) 0..1 arrays with each 2X2 subblock nonsingular and the array of 2X2 subblock determinants symmetric about the diagonal and antidiagonal.
Original entry on oeis.org
6, 24, 112, 974, 9928, 197152, 4547688, 200947508, 10553936856, 1051895421812, 125339066655024, 28078885802576900, 7575400864257725704
Offset: 1
Some solutions for 4X4
..1..0..1..0....0..1..1..1....0..1..0..1....1..1..1..0....1..1..1..1
..1..1..1..1....1..1..0..1....1..1..1..0....0..1..0..1....1..0..1..0
..1..0..1..0....1..0..1..1....0..1..0..1....1..0..1..0....0..1..0..1
..0..1..0..1....0..1..1..0....1..1..1..0....1..1..0..1....1..1..1..1
A187669
Number of (n+1)X(n+1) 0..2 arrays with each 2X2 subblock nonsingular and the array of 2X2 subblock determinants symmetric about the diagonal and antidiagonal.
Original entry on oeis.org
50, 550, 11282, 612204, 65533922, 18950885038
Offset: 1
Some solutions for 4X4
..1..0..1..2....2..0..2..1....1..1..2..0....2..2..2..2....1..0..1..0
..2..2..0..2....2..1..0..2....1..2..1..2....2..1..0..2....1..2..0..1
..1..0..1..2....2..0..1..1....2..1..2..1....2..0..1..2....1..0..2..1
..0..2..0..2....1..2..0..2....0..2..1..1....1..2..2..2....0..1..0..1
A187672
Number of 4X4 0..n arrays with each 2X2 subblock nonsingular and the array of 2X2 subblock determinants symmetric about the diagonal and antidiagonal.
Original entry on oeis.org
112, 11282, 174292, 1549398, 6839146, 32368980, 88344978, 268011840
Offset: 1
Some n=3 solutions for 4X4
..0..1..1..2....0..2..2..2....0..2..2..3....0..2..2..2....2..1..1..2
..2..0..2..3....2..0..3..0....2..0..2..1....3..0..3..1....1..0..2..2
..3..1..0..1....2..3..0..2....0..2..0..2....0..2..0..2....2..2..0..1
..1..0..2..1....2..0..2..1....2..2..2..1....2..1..3..3....3..2..1..3
Showing 1-4 of 4 results.
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