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A187164
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Number of 3-step self-avoiding walks on an n X n X n cube summed over all starting positions.
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2
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0, 48, 342, 1056, 2370, 4464, 7518, 11712, 17226, 24240, 32934, 43488, 56082, 70896, 88110, 107904, 130458, 155952, 184566, 216480, 251874, 290928, 333822, 380736, 431850, 487344, 547398, 612192, 681906, 756720, 836814, 922368, 1013562, 1110576
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OFFSET
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1,2
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COMMENTS
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LINKS
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FORMULA
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Empirical: a(n) = 30*n^3 - 60*n^2 + 24*n for n>1.
G.f.: 6*x^2*(8 + 25*x - 4*x^2 + x^3) / (1 - x)^4.
a(n) = 4*a(n-1) - 6*a(n-2) + 4*a(n-3) - a(n-4) for n>5.
(End)
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EXAMPLE
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A solution for 2 X 2 X 2:
..0..0.....0..0
..1..2.....0..3
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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