A223645 Number of (n+2)X1 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

3, 5, 13, 27, 60, 119, 251, 477, 1001, 2011, 4034, 7901, 16302, 32324, 64879, 130246, 260340, 521049, 1046933, 2077633, 4177166, 8376165, 16722144, 33343800, 67054762, 133875590, 267805425, 536072391, 1071591827, 2143497919, 4292483722

Offset

1,1

Comments

Column 1 of A223652

Links

R. H. Hardin, Table of n, a(n) for n = 1..120

Example

All solutions for n=3
..0....1....1....0....1....1....1....1....1....1....0....1....1
..0....0....0....0....1....1....1....0....1....0....1....0....0
..0....0....0....0....0....0....0....0....1....1....0....0....1
..1....1....1....0....0....0....1....0....0....1....0....0....0
..1....0....1....1....0....1....1....0....1....1....1....1....1

Crossrefs

Sequence in context: A288827 A084173 A354951 * A190570 A337860 A000631

Adjacent sequences: A223642 A223643 A223644 * A223646 A223647 A223648

Keyword

nonn

Author

R. H. Hardin Mar 25 2013

Status

approved