A267018 Number of n X n arrays containing n copies of 0..n-1 with every element equal to or 1 greater than any northeast or northwest neighbors modulo n and the upper left element equal to 0.
1, 3, 15, 137, 2063, 69265, 4893787, 787556232
Offset: 1
Keywords
Examples
Some solutions for n=4 ..0..3..1..3....0..1..3..2....0..2..0..1....0..3..1..2....0..2..0..3 ..3..1..0..2....1..0..2..3....2..0..2..1....3..1..3..1....2..1..3..1 ..2..0..2..0....1..2..0..3....0..3..1..3....2..0..1..3....1..3..1..0 ..1..3..1..2....2..1..3..0....3..1..3..2....0..2..0..2....3..2..0..2
Crossrefs
Cf. A267020.
Comments