A223389 Number of (n+2)X2 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

121, 961, 11025, 116964, 1089936, 9979281, 94770225, 801003204, 7591462641, 69950728324, 621964090609, 5519172901264, 51216422599225, 457387771663876, 4124085740712025, 37288268087703616, 334946028515357961

Offset

1,1

Comments

Column 2 of A223391

Links

R. H. Hardin, Table of n, a(n) for n = 1..25

Example

Some solutions for n=1
..2..2....1..2....0..1....2..0....2..2....1..2....2..0....1..0....2..2....1..2
..0..0....1..0....0..0....1..0....0..0....0..1....0..0....0..0....0..0....0..0
..1..2....2..2....1..2....1..2....0..2....1..1....0..1....2..1....0..1....0..1

Crossrefs

Sequence in context: A203959 A362319 A211472 * A243810 A302561 A120353

Adjacent sequences: A223386 A223387 A223388 * A223390 A223391 A223392

Keyword

nonn

Author

R. H. Hardin Mar 19 2013

Status

approved