A211888 T(n,k)=Number of lower triangular n X n arrays of integers 0 upwards introduced in row major order, with each element unique in its row and column, and containing the value n(n+1)/2-k-1

0, 0, 2, 0, 2, 8, 0, 0, 19, 26, 0, 0, 22, 236, 66, 0, 0, 22, 957, 1726, 141, 0, 0, 22, 1942, 23267, 8471, 267, 0, 0, 0, 2382, 176941, 285622, 31732, 463, 0, 0, 0, 2418, 787584, 5996922, 2223733

Offset

1,3

Comments

Table starts

...0.....0.......0.......0......0....0.0.0.0

...2.....2.......0.......0......0....0.0.0

...8....19......22......22.....22....0.0

..26...236.....957....1942...2382.2418

..66..1726...23267..176941.787584

.141..8471..285622.5996922

.267.31732.2223733

.463

Links

Table of n, a(n) for n=1..43.

Example

Some solutions for n=4 k=4
..0........0........0........0........0........0........0........0
..1.0......1.0......1.2......1.2......1.2......1.2......1.2......1.2
..2.3.1....2.3.4....3.0.1....3.1.4....3.4.1....3.4.2....3.4.5....3.0.4
..4.1.0.5..3.5.2.0..2.3.4.5..4.0.1.5..4.1.5.0..4.0.5.2..2.0.4.3..5.6.7.2

Crossrefs

Sequence in context: A235712 A154852 A088996 * A350601 A293783 A274541

Adjacent sequences: A211885 A211886 A211887 * A211889 A211890 A211891

Keyword

nonn,tabl

Author

R. H. Hardin Apr 24 2012

Status

approved