A233255 Number of n X 7 0..5 arrays with no element x(i,j) adjacent to itself or value 5-x(i,j) horizontally or antidiagonally, top left element zero, and 1 appearing before 2 3 and 4, and 2 appearing before 3 in row major order (unlabelled 6-colorings with no clashing color pairs).

528, 1992704, 8050180096, 32835998056448, 134179300927602688, 548491734506604068864, 2242238966451009797226496, 9166394920089108387649814528, 37472795110784044637628292661248

Offset

1,1

Comments

Column 7 of A233256.

Links

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

Formula

Empirical: a(n) = 5504*a(n-1) -6438912*a(n-2) +2774532096*a(n-3) -478351982592*a(n-4) +27831388078080*a(n-5).

Example

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

Crossrefs

Cf. A233256.

Sequence in context: A263909 A233173 A233128 * A204684 A205160 A205309

Adjacent sequences: A233252 A233253 A233254 * A233256 A233257 A233258

Keyword

nonn

Author

R. H. Hardin, Dec 06 2013

Status

approved