A223375 3X3 square grid graph coloring a rectangular array: number of nX4 0..8 arrays where 0..8 label nodes of the square grid graph and every array movement to a horizontal or vertical neighbor moves along an edge of this graph

192, 5808, 192752, 6443888, 215773456, 7226963248, 242067684912, 8108163611488, 271587161033712, 9096958174072272, 304707548044067088, 10206344863862297360, 341867068221933149936, 11451023265896103018864

Offset

1,1

Comments

Column 4 of A223379

Links

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

Formula

Empirical: a(n) = 43*a(n-1) -319*a(n-2) -105*a(n-3) +4371*a(n-4) -4177*a(n-5) -9101*a(n-6) +12732*a(n-7) -5244*a(n-8) +704*a(n-9)

Example

Some solutions for n=3
..2..1..2..5....3..4..7..6....1..4..3..0....1..4..5..4....1..0..3..6
..5..4..5..8....4..5..4..7....4..3..4..3....4..3..4..7....0..3..6..3
..2..5..2..5....7..4..3..4....3..6..3..4....3..4..5..8....3..6..7..4
Vertex neighbors:
0 -> 1 3
1 -> 0 2 4
2 -> 1 5
3 -> 0 4 6
4 -> 3 1 5 7
5 -> 4 2 8
6 -> 3 7
7 -> 6 4 8
8 -> 7 5

Crossrefs

Sequence in context: A299863 A223421 A230751 * A233154 A292076 A223214

Adjacent sequences: A223372 A223373 A223374 * A223376 A223377 A223378

Keyword

nonn

Author

R. H. Hardin Mar 19 2013

Status

approved