A223155 Number of (n+2)X3 0..2 arrays with all rows and columns having a strictly positive second derivative in a quadratic least squares fit

99, 989, 16089, 215563, 2616383, 31465359, 363006521, 3765617353, 43008488235, 509667805085, 5518115942960, 58959131052620

Offset

1,1

Comments

Column 1 of A223157

Links

Table of n, a(n) for n=1..12.

Example

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

Crossrefs

Sequence in context: A182672 A124113 A223157 * A308466 A093299 A196645

Adjacent sequences: A223152 A223153 A223154 * A223156 A223157 A223158

Keyword

nonn

Author

R. H. Hardin Mar 16 2013

Status

approved