A223929 Number of nX4 0..2 arrays with rows, columns and antidiagonals unimodal and diagonals nondecreasing

46, 698, 4498, 21334, 86439, 316136, 1065625, 3337831, 9773219, 26903878, 70024867, 173255292, 409514526, 928832014, 2029581476, 4287303027, 8781854785, 17488776976, 33939319272, 64311697250, 119202262153, 216450903569

Offset

1,1

Comments

Column 4 of A223933

Links

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

Formula

Empirical: a(n) = (1/106748928000)*n^16 + (1/13343616000)*n^15 + (1/116756640)*n^14 + (4003/37362124800)*n^13 + (97199/28740096000)*n^12 + (670871/14370048000)*n^11 + (94057/130636800)*n^10 - (113957/261273600)*n^9 + (565001317/5225472000)*n^8 - (887457691/1306368000)*n^7 + (3190047029/359251200)*n^6 - (36838723231/718502400)*n^5 + (4745796217531/15567552000)*n^4 - (170787179737/162162000)*n^3 + (51300697729/21621600)*n^2 - (74839579/180180)*n - 7017 for n>6

Example

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

Crossrefs

Sequence in context: A200898 A160151 A278204 * A224053 A224306 A224370

Adjacent sequences: A223926 A223927 A223928 * A223930 A223931 A223932

Keyword

nonn

Author

R. H. Hardin Mar 29 2013

Status

approved