A187670 T(n,k)=Number of (n+1)X(n+1) 0..k arrays with each 2X2 subblock nonsingular and the array of 2X2 subblock determinants symmetric about the diagonal and antidiagonal.

6, 50, 24, 192, 550, 112, 512, 4044, 11282, 974, 1126, 17716, 174292, 612204, 9928, 2146, 56080, 1549398, 36461174, 65533922, 197152, 3760, 150166, 6839146, 835707780

Offset: 1

Author

R. H. Hardin Mar 12 2011

Keywords

• nonn
• tabl

Comments

Table starts

......6.......50......192.......512....1126...2146.3760

.....24......550.....4044.....17716...56080.150166

....112....11282...174292...1549398.6839146

....974...612204.36461174.835707780

...9928.65533922

.197152

Examples

			Some k=3 solutions for 5X5
..0..2..2..0..3....0..2..2..2..3....0..2..2..2..1....0..2..2..2..3
..2..1..0..1..0....2..2..0..1..1....2..2..0..1..1....2..2..0..1..1
..2..0..3..0..2....2..0..2..0..2....2..0..1..1..3....2..0..1..0..2
..0..1..0..1..2....0..1..0..2..2....3..1..0..2..2....0..1..0..2..3
..3..2..2..2..0....1..1..2..3..1....2..1..2..2..0....1..1..2..2..1
		

Crossrefs

Row 1 is A062801