Number of nX2 0..3 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.
A223404
Number of nX2 0..3 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) =16a(1) =256a(2) =1296a(3) =22500a(4) =311364a(5) =4519876a(6) =71910400a(7) =1131582321a(8) =17402886400a(9) =291627000625
External references
- oeis: A223404