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A223426
5X5X5 triangular graph without horizontal edges coloring a rectangular array: number of nX2 0..14 arrays where 0..14 label nodes of a graph with edges 0,1 0,2 1,3 1,4 2,4 2,5 3,6 3,7 4,7 4,8 5,8 5,9 6,10 6,11 7,11 7,12 8,12 8,13 9,13 9,14 and every array movement to a horizontal or vertical neighbor moves along an edge of this graph
1
40, 248, 1648, 11168, 76384, 524736, 3613024, 24906592, 171802144, 1185459328, 8181293568, 56467581344, 389761873696, 2690371352800, 18570868118560, 128190601161344, 884876042394432, 6108154188923040, 42163659349783904
OFFSET
1,1
COMMENTS
Column 2 of A223432
LINKS
FORMULA
Empirical: a(n) = 14*a(n-1) -57*a(n-2) +28*a(n-3) +225*a(n-4) -230*a(n-5) -192*a(n-6) +232*a(n-7) +28*a(n-8) -48*a(n-9)
EXAMPLE
Some solutions for n=3
..4..2....2..5....7..3....9..5....7.11....8.12....4..2....4..2....3..1....8..4
..2..0....5..2....3..6...14..9....4..7....5..8....2..5....7..4....1..0....5..8
..4..2....9..5....7.11....9..5....8.12....8.13....0..2....3..7....4..1....8..4
CROSSREFS
Sequence in context: A073962 A267391 A229632 * A290127 A115170 A374240
KEYWORD
nonn
AUTHOR
R. H. Hardin Mar 20 2013
STATUS
approved