A223194 - OEIS

A223194

Number of nX7 0..2 arrays with all rows and columns having a nonnegative second derivative in a quadratic least squares fit, with one and two element arrays taken as having a zero second derivative

1143, 1306449, 52906752, 76015542500, 49198404222036, 36214510060655577, 36869649918720635277

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OFFSET

1,1

COMMENTS

Column 7 of A223195

LINKS

Table of n, a(n) for n=1..7.

EXAMPLE

Some solutions for n=3

..0..0..0..2..0..1..2....0..0..0..1..2..2..2....0..0..1..0..2..2..2

..0..0..0..1..0..1..1....0..0..0..0..1..1..2....0..0..0..0..0..1..0

..2..0..0..2..0..2..1....0..0..0..0..1..1..2....2..0..0..2..0..2..0

CROSSREFS

Sequence in context: A252428 A251773 A116174 * A265504 A237458 A202312

Adjacent sequences: A223191 A223192 A223193 * A223195 A223196 A223197

KEYWORD

nonn

AUTHOR

R. H. Hardin Mar 18 2013

STATUS

approved