Number of 3Xn 0..1 arrays with all rows having a nonnegative second derivative, and all and 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.
A223653
Number of 3Xn 0..1 arrays with all rows having a nonnegative second derivative, and all and 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.
Terms
- a(0) =3a(1) =9a(2) =9a(3) =35a(4) =77a(5) =207a(6) =513a(7) =1415a(8) =4009a(9) =12499a(10) =37577a(11) =99863a(12) =300723a(13) =949821a(14) =2565811a(15) =7925175a(16) =23158917a(17) =68824353a(18) =207493163a(19) =617410067a(20) =1841509697a(21) =5611469021a(22) =16589242023a(23) =49212663699a(24) =148570250829a(25) =449163990819
External references
- oeis: A223653