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A223657 Number of 7Xn 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 0
60, 3600, 10425, 1059839, 24559913, 1119629805, 47882329200, 2061491256869, 95329202955957, 6980023496929171, 335311367775542739, 17119067750905601475, 1054799368422675063804, 74856492204365399292957 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Row 5 of A223652

LINKS

Table of n, a(n) for n=1..14.

EXAMPLE

Some solutions for n=3

..0..0..1....1..1..1....1..1..1....1..1..1....0..0..1....1..0..1....1..0..1

..0..0..1....0..0..1....1..0..1....0..0..0....1..0..1....0..0..0....1..1..1

..0..0..0....0..0..0....0..0..1....1..0..0....1..1..1....0..0..1....0..0..0

..0..0..0....0..0..1....0..0..0....1..1..1....0..0..1....0..0..1....0..0..0

..1..0..0....1..0..0....0..0..1....0..0..1....0..0..0....1..0..0....1..0..0

..1..0..0....0..0..1....0..0..0....1..1..1....0..0..0....0..0..0....0..0..0

..1..1..1....0..0..0....1..0..1....1..0..1....1..1..1....1..1..1....1..1..1

CROSSREFS

Sequence in context: A180373 A264947 A004297 * A264369 A053401 A267930

Adjacent sequences:  A223654 A223655 A223656 * A223658 A223659 A223660

KEYWORD

nonn

AUTHOR

R. H. Hardin Mar 25 2013

STATUS

approved

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Last modified December 4 02:40 EST 2021. Contains 349469 sequences. (Running on oeis4.)