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A187166
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Number of 5-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, 3240, 14256, 37470, 77184, 137754, 223536, 338886, 488160, 675714, 905904, 1183086, 1511616, 1895850, 2340144, 2848854, 3426336, 4076946, 4805040, 5614974, 6511104, 7497786, 8579376, 9760230, 11044704, 12437154, 13941936, 15563406
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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) = 726*n^3 - 2640*n^2 + 2688*n - 720 for n>3.
G.f.: 6*x^2*(24 + 444*x + 360*x^2 - 115*x^3 + 4*x^4 + 9*x^5) / (1 - x)^4.
a(n) = 4*a(n-1) - 6*a(n-2) + 4*a(n-3) - a(n-4) for n>7.
(End)
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EXAMPLE
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A solution for 2 X 2 X 2:
..5..0.....4..1
..0..0.....3..2
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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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