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A223421
3-level binary fanout graph coloring a rectangular array: number of nX6 0..6 arrays where 0..6 label nodes of a graph with edges 0,1 1,3 1,4 0,2 2,5 2,6 and every array movement to a horizontal or vertical neighbor moves along an edge of this graph
1
192, 5408, 163168, 4934272, 150006016, 4565849088, 139114196992, 4240305623040, 129279082045440, 3941937218551808, 120203880286208000, 3665566262474506240, 111781755512338644992, 3408823463373890650112, 103953721139031970938880
OFFSET
1,1
COMMENTS
Column 6 of A223423
LINKS
FORMULA
Empirical: a(n) = 48*a(n-1) -460*a(n-2) -4144*a(n-3) +60160*a(n-4) -27456*a(n-5) -1549312*a(n-6) +3687168*a(n-7) +10996224*a(n-8) -43337728*a(n-9) -1603584*a(n-10) +149012480*a(n-11) -140541952*a(n-12) -92667904*a(n-13) +182190080*a(n-14) -52166656*a(n-15) -28835840*a(n-16) +16777216*a(n-17) -2097152*a(n-18)
EXAMPLE
Some solutions for n=3
..0..2..6..2..0..2....0..2..6..2..0..2....1..0..2..6..2..0....0..2..6..2..6..2
..2..5..2..6..2..6....2..6..2..0..1..0....0..1..0..2..5..2....2..6..2..0..2..6
..0..2..5..2..6..2....5..2..0..2..0..2....2..0..2..0..2..0....5..2..0..2..0..2
CROSSREFS
Sequence in context: A209594 A168635 A299863 * A230751 A223375 A233154
KEYWORD
nonn
AUTHOR
R. H. Hardin Mar 20 2013
STATUS
approved