A223180 Rolling icosahedron footprints: number of n X n 0..11 arrays starting with 0 where 0..11 label vertices of an icosahedron and every array movement to a horizontal, vertical or antidiagonal neighbor moves along an icosahedral edge.

1, 20, 400, 14560, 1018720, 141047120, 39288329040, 22231433842560, 25710310945249680, 61010814457361940400

Offset: 1

Author

R. H. Hardin, Mar 18 2013

Keywords

• nonn

Comments

Diagonal of A223186.

Examples

			Some solutions for n=3
..0..7..1....0..5..7....0..1..7....0..1..7....0..2..6....0..7..1....0..7.11
..5..0..7....7..0..1....7..3.11....7..3..1....6..4..2....5..0..7....1..3..7
..7..1..3....1..7..3...11..7..5....1..8..3....2..6..4....7..5.11....7..1..0
Vertex neighbors:
0 -> 1 2 5 6 7
1 -> 0 2 3 7 8
2 -> 0 1 4 6 8
3 -> 1 7 8 9 11
4 -> 2 6 8 9 10
5 -> 0 6 7 10 11
6 -> 0 2 4 5 10
7 -> 0 1 3 5 11
8 -> 1 2 3 4 9
9 -> 3 4 8 10 11
10 -> 4 5 6 9 11
11 -> 3 5 7 9 10
		

Crossrefs

Cf. A223186.