A223966 Number of 6Xn 0..3 arrays with antidiagonals unimodal and rows and diagonals nondecreasing

4096, 403104, 5777663, 37844037, 163752797, 556027700, 1629022329, 4351046624, 10953882109, 26519610433, 62472567689, 144124515790, 326646013571, 728132468716, 1596498777021, 3441674914130, 7290815852670, 15169818503342

Offset

1,1

Comments

Row 6 of A223961

Links

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

Formula

Empirical: a(n) = (1/73156608000)*n^18 + (1/2709504000)*n^17 + (3319/268240896000)*n^16 + (247579/871782912000)*n^15 + (1111849/193729536000)*n^14 + (3684553/35582976000)*n^13 + (658841977/402361344000)*n^12 + (521443357/22353408000)*n^11 + (7665391471/24385536000)*n^10 + (90826901857/24385536000)*n^9 + (333381059779/8128512000)*n^8 + (85061672873/217728000)*n^7 + (319642737999043/100590336000)*n^6 + (118989237432757/5588352000)*n^5 + (107614272658699/1862784000)*n^4 + (891088311042211/9081072000)*n^3 - (51719689062621/11211200)*n^2 + (1774047167507/360360)*n + 34898064 for n>11

Example

Some solutions for n=3
..0..0..0....0..0..2....0..0..0....0..0..0....0..0..0....0..0..0....0..0..0
..0..0..0....0..0..1....0..0..1....0..0..0....0..0..1....0..0..0....0..0..0
..0..1..1....0..1..1....2..2..3....0..0..2....0..2..2....0..0..0....0..0..2
..0..1..3....1..1..2....0..2..2....0..1..2....0..3..3....0..2..2....1..1..3
..0..0..2....0..1..2....0..1..2....0..0..3....2..2..3....1..2..3....1..3..3
..0..1..3....0..2..2....0..2..2....0..1..1....0..2..2....1..2..2....1..2..3

Crossrefs

Sequence in context: A016806 A231844 A232961 * A195660 A321836 A016902

Adjacent sequences: A223963 A223964 A223965 * A223967 A223968 A223969

Keyword

nonn

Author

R. H. Hardin Mar 29 2013

Status

approved