A233169 Number of n X n 0..5 arrays with no element x(i,j) adjacent to itself or value 5-x(i,j) horizontally, diagonally or antidiagonally, top left element zero, and 1 appearing before 2 3 and 4, and 2 appearing before 3 in row major order (unlabelled 6-colorings with no clashing color pairs).
1, 8, 2688, 7938048, 221463445504, 48667983827959808, 95229762257179140685824, 1517114635517382193142028042240, 212050285595421539693130354498977398784, 244891984772140151804896156943078190424499683328
Offset: 1
Keywords
Examples
Some solutions for n=3 ..0..1..2....0..1..2....0..1..2....0..1..5....0..1..5....0..1..2....0..1..0 ..2..4..2....5..1..5....2..1..3....5..4..0....0..4..2....0..4..5....0..2..0 ..3..4..5....2..4..0....2..4..2....2..4..2....5..4..2....3..1..2....5..3..4
Links
- R. H. Hardin, Table of n, a(n) for n = 1..13
Comments