A223288 Rolling icosahedron face footprints: number of 7Xn 0..19 arrays starting with 0 where 0..19 label faces of an icosahedron and every array movement to a horizontal, diagonal or antidiagonal neighbor moves across an icosahedral edge

64000000, 46875, 7740273, 221142771, 22392745881, 895927195659, 72981761306721, 3419190010701027, 246223435310438889, 12650585205686219643, 846009017331144444849, 45987344869442894841555, 2939800653860874208317369

Offset

1,1

Comments

Row 7 of A223282

Links

R. H. Hardin, Table of n, a(n) for n = 1..32

Example

Some solutions for n=3
..0..5..0....0..5..0....0..5..0....0..5..0....0..5..0....0..5..0....0..5..0
..0..1..0....0..1..0....0..1..0....0..1..0....0..1..0....0..1..0....0..1..0
..4..1..4....4..1..0....6..1..0....0..5..0....0..5..0....0..2..0....6..1..4
..0..1..0....4..1..0....0..1..6....0..5..0....9..5..7....0..2..8....0..1..0
..0..1..0....0..1..0....6..1..6....0..5..0....9..5..7....8..2..8....0..1..4
..0..1..0....0..2..0....4..1..6....7..5..9....0..5..0....8.13..8....0..1..4
..6..1..4....0..2..3....6..1..6....7..5..7....9..5..9...16.13..8....6..1..0
Face neighbors:
0 -> 1 2 5
1 -> 0 4 6
2 -> 0 3 8
3 -> 2 4 16
4 -> 3 1 17
5 -> 0 7 9
6 -> 1 7 10
7 -> 6 5 11
8 -> 2 9 13
9 -> 8 5 14
10 -> 6 12 17
11 -> 7 12 14
12 -> 11 10 19
13 -> 8 15 16
14 -> 9 11 15
15 -> 14 13 19
16 -> 3 13 18
17 -> 4 10 18
18 -> 16 17 19
19 -> 15 18 12

Crossrefs

Sequence in context: A116499 A217937 A203932 * A223485 A250863 A348276

Adjacent sequences: A223285 A223286 A223287 * A223289 A223290 A223291

Keyword

nonn

Author

R. H. Hardin Mar 19 2013

Status

approved