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A223689
Petersen graph (8,2) coloring a rectangular array: number of nX5 0..15 arrays where 0..15 label nodes of a graph with edges 0,1 0,8 8,14 8,10 1,2 1,9 9,15 9,11 2,3 2,10 10,12 3,4 3,11 11,13 4,5 4,12 12,14 5,6 5,13 13,15 6,7 6,14 7,0 7,15 and every array movement to a horizontal or antidiagonal neighbor moves along an edge of this graph
1
1296, 66816, 3788640, 223096320, 13402129824, 814399853760, 49817845241568, 3059068970173824, 188252023352797728, 11599193857488796224, 715189042123683831648, 44115021488935804260096, 2721759594409941703146144
OFFSET
1,1
COMMENTS
Column 5 of A223692
LINKS
FORMULA
Empirical: a(n) = 144*a(n-1) -7582*a(n-2) +191344*a(n-3) -2550861*a(n-4) +18205352*a(n-5) -64961020*a(n-6) +89885952*a(n-7) for n>8
EXAMPLE
Some solutions for n=3
..0..1..9.15..7....0..8..0..1..0....0..8..0..1..0....0..1..9.15.13
..9.15..7.15..9...10..8..0..8.10....0..1..9..1..9....9.15.13.11.13
..9.15..7.15..9....0..8.10..2..3....9..1..9..1..9....7.15.13.15.13
CROSSREFS
Sequence in context: A017236 A265478 A017344 * A193153 A223273 A017464
KEYWORD
nonn
AUTHOR
R. H. Hardin Mar 25 2013
STATUS
approved