A223236 Rolling icosahedron footprints: number of 4Xn 0..11 arrays starting with 0 where 0..11 label vertices of an icosahedron and every array movement to a horizontal, diagonal or antidiagonal neighbor moves along an icosahedral edge.

1728, 10985, 812225, 32837285, 1697263985, 78951770585, 3843057179285, 183367303999865, 8826695677742465, 423223089093370325, 20328307272501475145, 975647469218575594625, 46842159188887320714725

Offset: 1

Author

R. H. Hardin Mar 18 2013

Keywords

• nonn

Comments

Row 4 of A223233

Examples

			Some solutions for n=3
..0..6.10....0..6..0....0..6..4....0..6.10....0..6.10....0..6..2....0..6..0
..4..6..4....0..7..0....4..6..2...10..6..0....4..6..0....0..6..2....4..6..0
..5..6..2....3..7..1....5..6..0....4..6..4....5..6..2....2..6..4....2..6..4
..5..0..2....5..7..3....5..6..0....5.10..5....2..6..0....5..6..0...10..6..4
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
		

Links

• R. H. Hardin, Table of n, a(n) for n = 1..210

Formula

Empirical: a(n) = 32*a(n-1) +1042*a(n-2) -11074*a(n-3) -125832*a(n-4) +1314816*a(n-5) -820893*a(n-6) -14900218*a(n-7) [phone]*a(n-8) [phone]*a(n-9) -33578064*a(n-10) -26034048*a(n-11) [phone]*a(n-12) for n>13