A252972 Number of nX4 nonnegative integer arrays with upper left 0 and lower right n+4-5 and value increasing by 0 or 1 with every step right or down

1, 13, 153, 1236, 6997, 30802, 112877, 359550, 1024773, 2667554, 6438457, 14575914, 31230978, 63789948, 124931040, 235737421, 430298389, 762367687, 1314817821, 2212837300, 3642069999, 5873199042, 9294839027, 14457028052, 22128113529

Offset

1,2

Comments

Column 4 of A252976

Links

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

Formula

Empirical: a(n) = (29/479001600)*n^12 + (29/8870400)*n^11 + (3083/43545600)*n^10 + (233/290304)*n^9 + (73739/14515200)*n^8 + (48151/2419200)*n^7 + (2494049/43545600)*n^6 + (31657/483840)*n^5 - (1169489/10886400)*n^4 - (1024151/1814400)*n^3 + (2116423/831600)*n^2 - (601/27720)*n - 1

Example

Some solutions for n=4
..0..1..1..1....0..1..2..3....0..0..0..1....0..1..2..2....0..0..1..2
..0..1..1..1....0..1..2..3....1..1..1..2....0..1..2..2....0..1..2..2
..0..1..2..2....1..2..2..3....2..2..2..2....1..1..2..3....1..2..2..2
..0..1..2..3....1..2..3..3....2..2..3..3....1..2..2..3....2..3..3..3

Crossrefs

Sequence in context: A097168 A305262 A296722 * A108366 A204766 A163415

Adjacent sequences: A252969 A252970 A252971 * A252973 A252974 A252975

Keyword

nonn

Author

R. H. Hardin, Dec 25 2014

Status

approved