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A223506
Petersen graph (3,1) coloring a rectangular array: number of 3 X n 0..5 arrays where 0..5 label nodes of a graph with edges 0,1 0,3 3,5 3,4 1,2 1,4 4,5 2,0 2,5 and every array movement to a horizontal, diagonal or antidiagonal neighbor moves along an edge of this graph, with the array starting at 0.
1
36, 121, 1519, 16323, 182901, 2030665, 22598167, 251348043, 2795984857, 31101456601, 345963177427, 3848382739711, 42808185822221, 476184598157809, 5296925638013539, 58921311528252323, 655421879453116645
OFFSET
1,1
COMMENTS
Row 3 of A223504.
LINKS
FORMULA
Empirical: a(n) = 12*a(n-1) - 4*a(n-2) - 73*a(n-3) + 103*a(n-4) - 23*a(n-5) - 16*a(n-6) + 4*a(n-7) for n>8.
Empirical g.f.: x*(36 - 311*x + 211*x^2 + 1207*x^3 - 1774*x^4 + 397*x^5 + 272*x^6 - 68*x^7) / (1 - 12*x + 4*x^2 + 73*x^3 - 103*x^4 + 23*x^5 + 16*x^6 - 4*x^7). - Colin Barker, Aug 21 2018
EXAMPLE
Some solutions for n=3:
..0..2..5....0..3..4....0..1..0....0..2..1....0..3..0....0..3..0....0..1..4
..1..2..1....0..3..5....4..1..4....0..2..1....5..2..0....4..1..0....4..3..4
..5..4..1....5..3..5....4..3..0....1..2..1....0..2..5....4..3..0....0..1..0
CROSSREFS
Cf. A223504.
Sequence in context: A278022 A333007 A016862 * A238037 A238032 A365506
KEYWORD
nonn
AUTHOR
R. H. Hardin, Mar 21 2013
STATUS
approved