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A145458
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Exponential transform of C(n,8) = A000581.
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1
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1, 0, 0, 0, 0, 0, 0, 0, 1, 9, 45, 165, 495, 1287, 3003, 6435, 19305, 243100, 3981978, 49959702, 498967170, 4190469570, 30728937690, 201931408074, 1213163827326, 6849350570700, 39615797628550, 296414654550300, 3418235092302030
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,10
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COMMENTS
| a(n) is the number of ways of placing n labeled balls into indistinguishable boxes, where in each filled box 8 balls are seen at the top.
a(n) is also the number of forests of labeled rooted trees of height at most 1, with n labels, where each root contains 8 labels.
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LINKS
| N. J. A. Sloane, Transforms
Index entries for sequences related to rooted trees
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MAPLE
| a:= proc(n) option remember; local j; `if` (n=0, 1, add (binomial (n-1, j-1) *binomial(j, 8) *a(n-j), j=1..n)) end: seq (a(n), n=0..35);
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CROSSREFS
| Cf. 8th column of A145460, A143398.
Sequence in context: A008491 A023034 A000581 * A145137 A144902 A128643
Adjacent sequences: A145455 A145456 A145457 * A145459 A145460 A145461
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KEYWORD
| nonn
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AUTHOR
| Alois P. Heinz (heinz(AT)hs-heilbronn.de), Oct 10 2008
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