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A261427
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Number of permutations p of [7n] without fixed points such that p^7 = Id.
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3
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1, 720, 889574400, 24825530695680000, 5290995845684330496000000, 5123434663327851951402516480000000, 16586604100059403377645257954741452800000000, 146550752102252281868362306608987740351496192000000000
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OFFSET
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0,2
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LINKS
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FORMULA
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a(n) = (7n)! * [x^(7n)] exp(x^7/7).
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MAPLE
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a:= proc(n) option remember; `if`(n=0, 1,
mul(7*n-i, i=1..6)*a(n-1))
end:
seq(a(n), n=0..10);
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CROSSREFS
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7-section of column k=7 of A261430.
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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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