A223376 3X3 square grid graph coloring a rectangular array: number of nX5 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

544, 37008, 2812608, 215773456, 16589428016, 1275808315376, 98124582178928, 7547020636487088, 580464274863214064, 44645287470831363696, 3433808133436891915472, 264104805258676364046000

Offset

1,1

Comments

Column 5 of A223379

Links

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

Formula

Empirical: a(n) = 6529*a(n-2) -3729898*a(n-4) +606147188*a(n-6) -37186782450*a(n-8) +998979380722*a(n-10) -12128079473561*a(n-12) +73825567196497*a(n-14) -244037398666282*a(n-16) +453145801165820*a(n-18) -474188974363940*a(n-20) +277662926324048*a(n-22) -88145495115904*a(n-24) +14048888263168*a(n-26) -876794757120*a(n-28) for n>29

Example

Some solutions for n=3
..0..1..0..3..0....0..1..4..1..0....0..3..6..7..4....0..3..4..7..8
..1..0..1..4..1....1..4..3..4..1....1..4..7..4..7....1..4..7..4..5
..4..3..4..1..4....4..5..4..5..4....4..7..6..3..4....2..5..4..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: A266136 A204724 A168564 * A022048 A107512 A264948

Adjacent sequences: A223373 A223374 A223375 * A223377 A223378 A223379

Keyword

nonn

Author

R. H. Hardin Mar 19 2013

Status

approved