A269504 Number of nX3 arrays containing 3 copies of 0..n-1 avoiding the pattern down-up in every row and column.
1, 14, 420, 18332, 1261420, 134871120, 21338020496
Offset: 1
Keywords
Examples
Some solutions for n=4 ..0..0..3. .0..2..1. .0..2..1. .2..2..1. .0..2..1. .0..0..1. .0..0..1 ..1..1..2. .0..3..1. .1..2..2. .0..2..3. .1..2..3. .3..2..2. .3..2..2 ..2..3..1. .1..3..3. .3..3..3. .0..3..1. .3..3..2. .1..3..2. .2..3..1 ..3..2..0. .0..2..2. .0..0..1. .1..3..0. .0..0..1. .1..3..0. .0..3..1
Crossrefs
Cf. A269505.
Comments