Number of (n+2)X3 0..2 arrays with all rows having a nonnegative second derivative, and all columns having a positive second derivative in a quadratic least squares fit, with one and two element arrays taken as having a zero second derivative.

A223390

Number of (n+2)X3 0..2 arrays with all rows having a nonnegative second derivative, and all columns having a positive second derivative in a quadratic least squares fit, with one and two element arrays taken as having a zero second derivative.