A202755 Number of nX7 nonnegative integer arrays with each row and column increasing from zero by 0 or 1

1, 7, 78, 1022, 13197, 150777, 1442764, 11408125, 75393424, 424992394, 2086954916, 9097630767, 35775808290, 128617512596, 427443971156, 1325376633243, 3864035126505, 10661515466643, 27995060608622, 70289431296342

Offset

1,2

Comments

Column 7 of A202756

Links

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

Formula

Empirical: a(n) = (1/1520925880320000)*n^21 + (1/14485008384000)*n^20 + (17/5431878144000)*n^19 + (41/517321728000)*n^18 + (10847/9053130240000)*n^17 + (73/6897623040)*n^16 + (3646499/76046294016000)*n^15 + (340729/3621252096000)*n^14 + (186024683/217275125760000)*n^13 + (282751/26873856000)*n^12 + (25808261/724250419200)*n^11 + (2895163/86220288000)*n^10 + (493582091273/760462940160000)*n^9 + (2226946937/1034643456000)*n^8 - (263782703/2715939072000)*n^7 + (3455599541/129330432000)*n^6 - (31330211789/754427520000)*n^5 + (2559599737/7185024000)*n^4 - (3245092381/7334712000)*n^3 + (7079701/6350400)*n^2 - (28181/27720)*n + 1

Example

Some solutions for n=5
..0..0..0..0..0..0..0....0..0..0..0..0..0..0....0..0..0..0..0..0..0
..0..0..0..0..1..1..1....0..0..0..0..0..0..1....0..0..0..0..0..0..1
..0..1..1..1..1..2..2....0..0..0..0..1..1..2....0..0..0..1..1..1..2
..0..1..1..2..2..3..3....0..0..1..1..1..2..3....0..0..1..1..1..1..2
..0..1..1..2..2..3..4....0..1..1..2..2..3..3....0..0..1..2..2..2..2

Crossrefs

Sequence in context: A133272 A186657 A079590 * A280518 A156714 A350964

Adjacent sequences: A202752 A202753 A202754 * A202756 A202757 A202758

Keyword

nonn

Author

R. H. Hardin Dec 23 2011

Status

approved