A223296 4-loop graph coloring a rectangular array: number of n X 7 0..8 arrays where 0..8 label nodes of a graph with edges 0,1 1,2 2,0 0,3 3,4 4,0 0,5 5,6 6,0 0,7 7,8 8,0 and every array movement to a horizontal or vertical neighbor moves along an edge of this graph.

11808, 6404184, 11864385048, 12730353920784, 25787363600621016, 27821347292299780344, 56395315109321439563328, 60846019870394597868335400, 123338668226195827949533410312, 133072588038583292864451480249888

Offset

1,1

Comments

Column 7 of A223297.

Links

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

Example

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

Crossrefs

Cf. A223297.

Sequence in context: A031868 A205630 A205332 * A110846 A071519 A294661

Adjacent sequences: A223293 A223294 A223295 * A223297 A223298 A223299

Keyword

nonn

Author

R. H. Hardin Mar 19 2013

Status

approved