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A029575
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Number of permutations of an n-set containing an 8-cycle.
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2
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0, 0, 0, 0, 0, 0, 0, 0, 5040, 45360, 453600, 4989600, 59875200, 778377600, 10897286400, 163459296000, 2451889440000, 41682120480000, 750278168640000, 14255285204160000, 285105704083200000, 5987219785747200000, 131718835286438400000, 3029533211588083200000
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OFFSET
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0,9
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LINKS
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FORMULA
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a(n) = n! * (1 - Sum_{k=0..floor(n/8)} (-1)^k/(k!*8^k) ).
a(n)/n! is asymptotic to 1-e^(-1/8).
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PROG
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(PARI) a(n) = n! * (1 - sum(k=0, floor(n/8), (-1)^k/(k!*8^k) ) ); \\ Michel Marcus, Aug 08 2013
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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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