Number of nX1 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.
A223403
Number of nX1 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) =4a(1) =16a(2) =36a(3) =150a(4) =558a(5) =2126a(6) =8480a(7) =33639a(8) =131920a(9) =540025a(10) =2122564a(11) =8415455a(12) =33814594a(13) =135946810a(14) =537839881a(15) =2157395672a(16) =8623989781a(17) =34438483139a(18) =137851777060a(19) =551209368188
External references
- oeis: A223403