A264999 Number of n X n arrays containing n copies of 0..n-1 with rows and columns nondecreasing.
1, 2, 7, 112, 4919, 1268728, 1001060834, 4031708477982
Offset: 1
Keywords
Examples
Some solutions for n=4 ..0..0..0..1....0..0..1..3....0..0..1..3....0..0..0..1....0..0..0..2 ..0..1..2..2....0..1..1..3....0..1..1..3....0..1..1..1....0..1..1..3 ..1..1..3..3....0..1..2..3....0..2..2..3....2..2..2..2....1..1..2..3 ..2..2..3..3....2..2..2..3....1..2..2..3....3..3..3..3....2..2..3..3
Crossrefs
Cf. A265005.
Comments