A223862 Number of nX6 0..3 arrays with rows and antidiagonals unimodal and columns nondecreasing

610, 52591, 1477240, 22852913, 243933798, 1989679315, 13140481520, 73068868012, 352040804450, 1502130487437, 5774921786002, 20281095690376, 65798275499953, 199037907806762, 565735226772194, 1520829902726663, 3888227083552907

Offset

1,1

Comments

Column 6 of A223864

Links

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

Formula

Empirical: a(n) = (42587101/1600593426432000)*n^18 + (42587101/44460928512000)*n^17 + (315292339/15692092416000)*n^16 + (41939983/145297152000)*n^15 + (4407829651/1426553856000)*n^14 + (41324477/1596672000)*n^13 + (19314677849/113164128000)*n^12 + (2898049019/3143448000)*n^11 + (876424981241/219469824000)*n^10 + (28801840747/2032128000)*n^9 + (50450804070829/1207084032000)*n^8 + (17909311831/177408000)*n^7 + (265168304450783/1471133664000)*n^6 + (27553165793177/163459296000)*n^5 - (2984221796923/29719872000)*n^4 - (816413565637/1009008000)*n^3 - (1198736836439/7718911200)*n^2 + (2348655877/471240)*n - 5035 for n>4

Example

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

Crossrefs

Sequence in context: A220568 A189455 A224171 * A223985 A224062 A224048

Adjacent sequences: A223859 A223860 A223861 * A223863 A223864 A223865

Keyword

nonn

Author

R. H. Hardin Mar 28 2013

Status

approved