A223922 Number of 5Xn 0..2 arrays with rows and antidiagonals unimodal and columns nondecreasing

21, 441, 5548, 48182, 319156, 1721356, 7906972, 31947798, 116289938, 388293504, 1205901516, 3520937666, 9746278721, 25746339006, 65246565981, 159287861727, 375892787585, 859832700375, 1910938878762, 4134527627922, 8723666100444

Offset

1,1

Comments

Row 5 of A223918

Links

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

Formula

Empirical: a(n) = (1/1379196149760000)*n^20 + (1/27583922995200)*n^19 + (67/43553562624000)*n^18 + (2203/50812489728000)*n^17 + (35813/34871316480000)*n^16 + (4723/232475443200)*n^15 + (2458331/6974263296000)*n^14 + (8083259/1494484992000)*n^13 + (508218079/6897623040000)*n^12 + (34902853/45984153600)*n^11 + (6145973531/1072963584000)*n^10 + (1981076359/59609088000)*n^9 + (981368164559/6538371840000)*n^8 + (7803754241/14944849920)*n^7 + (1568765927873/1120863744000)*n^6 + (533988456371/186810624000)*n^5 + (40563025942379/9262693440000)*n^4 + (15131959121/3087564480)*n^3 + (22082097187/5431826400)*n^2 + (196063237/116396280)*n + 1

Example

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

Crossrefs

Sequence in context: A224265 A206886 A188770 * A224350 A224192 A207184

Adjacent sequences: A223919 A223920 A223921 * A223923 A223924 A223925

Keyword

nonn

Author

R. H. Hardin Mar 29 2013

Status

approved