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A321382
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Number of permutations of 6 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, 48852, 8437796016, 5752866855116280, 12229789732207993835280, 68139526686950961449783790480, 873795428893219442649940388795690880, 23337489207354946577030915302871598795308160
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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..6} (-1)^(6-k) * binomial(5, 6-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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