login
This site is supported by donations to The OEIS Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A253010 Number of nX7 nonnegative integer arrays with upper left 0 and lower right its king-move distance away minus 3 and every value increasing by 0 or 1 with every step right, diagonally se or down 1
20, 231, 2902, 33533, 309990, 2327062, 14697256, 541365583, 9617848524, 90094114144, 499454404412, 1875291094664, 5288570216780, 12109231279152, 23836473347284, 42007667355832, 68169527721372, 103870860371584 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 7 of A253011

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..210

FORMULA

Empirical: a(n) = (774604193792/3)*n^3 - 8398560300416*n^2 + (277091586550828/3)*n - 343375674454152 for n>18

EXAMPLE

Some solutions for n=6

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

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

..0..0..1..1..1..1..2....0..0..0..1..1..2..3....0..0..0..1..1..1..2

..0..0..1..1..1..1..2....0..0..0..1..1..2..3....0..0..1..1..1..2..2

..0..1..1..1..2..2..2....0..1..1..1..1..2..3....0..0..1..1..1..2..2

..0..1..2..2..2..3..3....0..1..1..2..2..2..3....0..0..1..1..2..2..3

CROSSREFS

Sequence in context: A073386 A022648 A004315 * A074334 A163004 A278320

Adjacent sequences:  A253007 A253008 A253009 * A253011 A253012 A253013

KEYWORD

nonn

AUTHOR

R. H. Hardin, Dec 25 2014

STATUS

approved

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

License Agreements, Terms of Use, Privacy Policy. .

Last modified June 25 07:53 EDT 2019. Contains 324347 sequences. (Running on oeis4.)