A223645 - OEIS

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

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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