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.
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.
Terms
- a(0) =50a(1) =550a(2) =11282a(3) =612204a(4) =65533922a(5) =18950885038
External references
- oeis: A187669