A224169 Number of nX4 0..3 arrays with rows and antidiagonals unimodal and columns nondecreasing

130, 3526, 38561, 272130, 1460836, 6425876, 24197608, 80350989, 240416852, 658890738, 1675303647, 3992383968, 8991162356, 19265941324, 39500748718, 77861024489, 148143119762, 273013479180, 488783426991, 852309147046

Offset

1,1

Comments

Column 4 of A224173

Links

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

Formula

Empirical: a(n) = (3551/47900160)*n^12 + (17561/13305600)*n^11 + (376693/21772800)*n^10 + (106499/725760)*n^9 + (229093/290304)*n^8 + (4775993/1209600)*n^7 + (239805679/21772800)*n^6 + (2313469/80640)*n^5 + (85217281/1088640)*n^4 - (37150333/907200)*n^3 - (7297121/207900)*n^2 + (474241/1386)*n - 383 for n>3

Example

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

Crossrefs

Sequence in context: A271758 A228997 A168124 * A223860 A223983 A224060

Adjacent sequences: A224166 A224167 A224168 * A224170 A224171 A224172

Keyword

nonn

Author

R. H. Hardin Mar 31 2013

Status

approved