A223923 Number of 6Xn 0..2 arrays with rows and antidiagonals unimodal and columns nondecreasing

28, 784, 12752, 139925, 1147712, 7526024, 41334135, 196691651, 831996762, 3191126598, 11273703656, 37147879480, 115325935123, 340079259419, 958837466287, 2598467396144, 6797368250655, 17222433541791, 42380526618210

Offset

1,1

Comments

Row 6 of A223918

Links

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

Formula

Empirical: a(n) = (1/35608838483312640000)*n^24 + (1/593480641388544000)*n^23 + (1/11491439984640000)*n^22 + (2153/709596419051520000)*n^21 + (219067/2432902008176640000)*n^20 + (25141/11058645491712000)*n^19 + (7669183/149388719800320000)*n^18 + (2894807/2766457774080000)*n^17 + (345585431/17575143505920000)*n^16 + (19926331/58583811686400)*n^15 + (19845690451/3766102179840000)*n^14 + (29105209667/470762772480000)*n^13 + (9676615094071/17575143505920000)*n^12 + (3447815819587/878757175296000)*n^11 + (1672600520777/75107450880000)*n^10 + (40399178860907/399435079680000)*n^9 + (5902479263543591/16005934264320000)*n^8 + (857508181884829/800296713216000)*n^7 + (1309477651758586831/532197314288640000)*n^6 + (43433412218488139/9855505820160000)*n^5 + (4693314253940149/778066248960000)*n^4 + (1959925243391/320817246750)*n^3 + (12456072565753/2698531355520)*n^2 + (3225389971/1784742960)*n + 1

Example

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

Crossrefs

Sequence in context: A208032 A264368 A224266 * A224351 A224193 A224010

Adjacent sequences: A223920 A223921 A223922 * A223924 A223925 A223926

Keyword

nonn

Author

R. H. Hardin Mar 29 2013

Status

approved