|
| |
|
|
A223595
|
|
Petersen graph (8,2) coloring a rectangular array: number of nX4 0..15 arrays where 0..15 label nodes of a graph with edges 0,1 0,8 8,14 8,10 1,2 1,9 9,15 9,11 2,3 2,10 10,12 3,4 3,11 11,13 4,5 4,12 12,14 5,6 5,13 13,15 6,7 6,14 7,0 7,15 and every array movement to a horizontal, diagonal or antidiagonal neighbor moves along an edge of this graph
|
|
1
|
|
|
|
432, 6736, 122608, 2372080, 47659632, 982848688, 20631729648, 438231627440, 9379905920496, 201754894742320, 4353130535839216, 94109174401819824, 2037032269494019568, 44126508340010479152, 956337724569802746864
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
|
OFFSET
|
1,1
|
|
|
COMMENTS
|
Column 4 of A223599
|
|
|
LINKS
|
R. H. Hardin, Table of n, a(n) for n = 1..210
|
|
|
FORMULA
|
Empirical: a(n) = 45*a(n-1) -639*a(n-2) +2781*a(n-3) +4328*a(n-4) -42674*a(n-5) +32672*a(n-6) +131496*a(n-7) -190080*a(n-8) +31104*a(n-9)
|
|
|
EXAMPLE
|
Some solutions for n=3
.10.12.10.12...13.15.13..5...10..8.14.12....2..3..2.10...13.15..9.15
.10..8.14..8....9.11.13..5...10..8.14.12...11..3..2..3....9.11..9..1
.10..8.10.12....9.11.13.15....0..8.14..6....2..3..2.10...13.15..9..1
|
|
|
CROSSREFS
|
Sequence in context: A234405 A234400 A236279 * A223436 A230922 A109123
Adjacent sequences: A223592 A223593 A223594 * A223596 A223597 A223598
|
|
|
KEYWORD
|
nonn
|
|
|
AUTHOR
|
R. H. Hardin Mar 23 2013
|
|
|
STATUS
|
approved
|
| |
|
|
