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A187169
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Number of 8-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, 144, 67824, 608928, 2188608, 5299056, 10416624, 18026640, 28617228, 42676728, 60693480, 83155824, 110552100, 143370648, 182099808, 227227920, 279243324, 338634360, 405889368, 481496688, 565944660, 659721624, 763315920, 877215888
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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) = 81390*n^3 - 463074*n^2 + 801216*n - 418032 for n>6.
G.f.: 12*x^2*(12 + 5604*x + 28208*x^2 + 13272*x^3 - 6080*x^4 - 1320*x^5 + 748*x^6 + 233*x^7 + 18*x^8) / (1 - x)^4.
a(n) = 4*a(n-1) - 6*a(n-2) + 4*a(n-3) - a(n-4) for n>10.
(End)
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EXAMPLE
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A solution for 3 X 3 X 3:
..0..8..0.....2..7..0.....3..0..0
..0..0..0.....1..6..0.....4..5..0
..0..0..0.....0..0..0.....0..0..0
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CROSSREFS
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KEYWORD
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nonn,walk
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AUTHOR
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STATUS
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approved
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