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A322096
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Number of permutations of 8 copies of 1..n with no element equal to another within a distance of 1.
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2
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1, 0, 2, 2403588, 36734931452736, 3470403228952634903280, 1490944857678655357195402606800, 2315418264816304038508896461231618573280, 10937192762438008527903830198163831816546577931520
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OFFSET
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0,3
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LINKS
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FORMULA
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a(n) = Integral_{0..infinity} (Sum_{k=1..8} (-1)^(8-k) * binomial(7, 8-k) * x^k/k!)^n * exp(-x) dx.
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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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