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A223235 Rolling icosahedron footprints: number of 3 X n 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. 1
144, 845, 25225, 492365, 11043445, 236027705, 5127809545, 110781320885, 2397904326205, 51869658014705, 1122255717889585, 24279356422739885, 525283571663978725, 11364402460546714985, 245867265513538637785 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Row 3 of A223233.

LINKS

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

FORMULA

Empirical: a(n) = 18*a(n-1) + 103*a(n-2) - 552*a(n-3) + 540*a(n-4) for n>5.

Empirical g.f.: x*(144 - 1747*x - 4817*x^2 + 30768*x^3 - 28620*x^4) / (1 - 18*x - 103*x^2 + 552*x^3 - 540*x^4). - Colin Barker, Aug 17 2018

EXAMPLE

Some solutions for n=3:

..0..2..0....0..5..7....0..6..2....0..2..1....0..6..0....0..1..7....0..1..7

..0..5..0....0..5..6....0..6..5....1..2..6....0..6..0....0..1..3....0..1..8

.11..5..0....0..5..6....5..7..0....4..2..1....4..2..0....3..7..0....7..1..8

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. A223233.

Sequence in context: A237734 A234091 A234084 * A187301 A120089 A159748

Adjacent sequences:  A223232 A223233 A223234 * A223236 A223237 A223238

KEYWORD

nonn

AUTHOR

R. H. Hardin, Mar 18 2013

STATUS

approved

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Last modified September 19 11:27 EDT 2021. Contains 347556 sequences. (Running on oeis4.)