Number of n X n 0..2 arrays with all rows and columns having a nonnegative second derivative in a quadratic least squares fit, with one and two element arrays taken as having a zero second derivative.
A223187
Number of n X n 0..2 arrays with all rows and columns having a nonnegative second derivative in a quadratic least squares fit, with one and two element arrays taken as having a zero second derivative.
Terms
- a(0) =3a(1) =81a(2) =1138a(3) =1133664a(4) =3815358480
External references
- oeis: A223187