A187463 Number of 3X3 0..n arrays with all the 2X2 subblocks nonsingular and the array of 2X2 subblock determinants symmetric.

26, 1236, 13726, 84048, 325932, 1118854, 2843394, 6976192, 14900828, 30426976, 54176690, 102373984, 165774050, 274508960, 439528372, 685793860, 988022550, 1499573556, 2077344368, 3019161806, 4198346324, 5736736398, 7500683014

Offset: 1

Author

R. H. Hardin Mar 10 2011

Keywords

• nonn

Comments

Row 2 of A187462

Links

• R. H. Hardin, Table of n, a(n) for n = 1..40