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!)
A224150 Number of 6 X n 0..1 arrays with rows and antidiagonals unimodal and columns nondecreasing. 1
7, 49, 242, 930, 2985, 8375, 21183, 49365, 107697, 222603, 439909, 837071, 1542126, 2762572, 4828665, 8257309, 13844903, 22800305, 36932600, 58912756, 92633675, 143699769, 220085207, 333009601, 498091361, 736852507, 1078664659, 1563244537 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Row 6 of A224146.

LINKS

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

FORMULA

Empirical: a(n) = (1/479001600)*n^12 + (1/26611200)*n^11 + (43/43545600)*n^10 + (29/1451520)*n^9 + (5671/14515200)*n^8 + (2219/345600)*n^7 + (2174569/43545600)*n^6 + (116341/483840)*n^5 + (8531549/10886400)*n^4 + (2862857/1814400)*n^3 + (3602461/1663200)*n^2 + (2327/1980)*n + 1.

Conjectures from Colin Barker, Aug 28 2018: (Start)

G.f.: x*(7 - 42*x + 151*x^2 - 396*x^3 + 762*x^4 - 1076*x^5 + 1137*x^6 - 906*x^7 + 538*x^8 - 230*x^9 + 67*x^10 - 12*x^11 + x^12) / (1 - x)^13.

a(n) = 13*a(n-1) - 78*a(n-2) + 286*a(n-3) - 715*a(n-4) + 1287*a(n-5) - 1716*a(n-6) + 1716*a(n-7) - 1287*a(n-8) + 715*a(n-9) - 286*a(n-10) + 78*a(n-11) - 13*a(n-12) + a(n-13) for n>13.

(End)

EXAMPLE

Some solutions for n=3:

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

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

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

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

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

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

CROSSREFS

Cf. A224146.

Sequence in context: A207083 A207177 A207089 * A094430 A188561 A225013

Adjacent sequences:  A224147 A224148 A224149 * A224151 A224152 A224153

KEYWORD

nonn

AUTHOR

R. H. Hardin, Mar 31 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 May 17 05:58 EDT 2022. Contains 353730 sequences. (Running on oeis4.)