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A223239
3-loop graph coloring a rectangular array: number of n X n 0..6 arrays where 0..6 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 and every array movement to a horizontal or vertical neighbor moves along an edge of this graph
1
7, 102, 11538, 5336844, 22029652542, 372027916726176, 55925027353114184220, 34340768547284823444042060, 187665945665214485110913868661962, 4188970054368199574776535077321295822220
OFFSET
1,1
COMMENTS
Diagonal of A223247
LINKS
EXAMPLE
Some solutions for n=3
..0..1..0....1..0..6....4..0..6....3..0..5....2..0..1....4..0..5....2..0..4
..1..0..3....0..3..0....0..4..0....0..5..0....0..6..0....0..6..0....0..3..0
..0..3..4....1..0..6....5..0..3....4..0..6....6..0..5....6..0..2....6..0..3
CROSSREFS
Sequence in context: A358159 A203356 A346719 * A140633 A142400 A032460
KEYWORD
nonn
AUTHOR
R. H. Hardin Mar 18 2013
STATUS
approved