login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A223654 Number of 4Xn 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
5, 25, 43, 229, 799, 3237, 16975, 58813, 262975, 1273157, 6142655, 26877117, 132748947, 716258257, 3072240791, 15826485913, 73962438259, 366204124645, 1830090585655, 8942164068501, 44436414147403, 225094702418657 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
Row 2 of A223652
LINKS
EXAMPLE
Some solutions for n=3
..1..0..1....1..0..1....1..1..1....1..1..1....1..1..1....1..1..1....1..1..1
..0..0..1....0..0..0....1..1..1....0..0..0....0..0..0....1..0..1....0..0..0
..1..0..0....0..0..1....0..0..0....0..0..0....1..0..0....0..0..0....1..0..1
..1..1..1....1..1..1....1..1..1....0..0..0....1..1..1....1..0..1....1..0..1
CROSSREFS
Sequence in context: A294256 A056872 A029490 * A362092 A098947 A364584
KEYWORD
nonn
AUTHOR
R. H. Hardin Mar 25 2013
STATUS
approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified February 24 14:26 EST 2024. Contains 370305 sequences. (Running on oeis4.)