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!)
A224375 Number of 3Xn 0..2 arrays with rows unimodal and antidiagonals nondecreasing 1
27, 324, 1838, 7608, 26314, 80819, 227112, 593400, 1455898, 3378085, 7455007, 15725041, 31840088, 62123439, 117194882, 214407666, 381424761, 661365902, 1120086056, 1856304530, 3015496746, 4808693047, 7537606592, 11627841824 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Row 3 of A224374

LINKS

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

FORMULA

Empirical: a(n) = (1/19160064)*n^12 + (1/456192)*n^11 + (2287/43545600)*n^10 + (215/290304)*n^9 + (20603/2903040)*n^8 + (923/17920)*n^7 + (14627101/43545600)*n^6 + (400091/207360)*n^5 + (16965289/2177280)*n^4 + (3069023/362880)*n^3 + (13912639/1663200)*n^2 + (21001/3465)*n - 6

EXAMPLE

Some solutions for n=3

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

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

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

CROSSREFS

Sequence in context: A231911 A182130 A224311 * A010832 A022719 A290405

Adjacent sequences:  A224372 A224373 A224374 * A224376 A224377 A224378

KEYWORD

nonn

AUTHOR

R. H. Hardin Apr 05 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 June 28 01:48 EDT 2022. Contains 354903 sequences. (Running on oeis4.)