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A124778
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Number of unlabeled unordered rooted forests associated with compositions in standard order.
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0
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1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 2, 1, 2, 2, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1
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OFFSET
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0,11
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COMMENTS
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The standard order of compositions is given by A066099.
The k-th term of the composition is the number of objects at height k; in particular, the first term is the number of trees.
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LINKS
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Table of n, a(n) for n=0..31.
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EXAMPLE
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Composition number 11 is 2,1,1; there is only 1 forest associated with this (shown below), so a(11) = 1.
O..
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O..
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O.O
The table starts:
1
1
1 1
1 1 1 1
1 1 2 1 1 1 1 1
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CROSSREFS
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Cf. A066099, A011782 (row lengths), A000081 (row sums).
Sequence in context: A056059 A158819 A031279 * A037831 A188169 A107039
Adjacent sequences: A124775 A124776 A124777 * A124779 A124780 A124781
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KEYWORD
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more,nonn,tabf
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AUTHOR
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Franklin T. Adams-Watters, Nov 06 2006
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STATUS
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approved
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